Update server.js

[bluzi]

No description provided.

[TravisBuddy]

Travis tests have failed

Hey Eliran Pe'er,
Please read the following log in order to understand the failure reason.
It'll be awesome if you fix what's wrong and commit the changes.

npm run-script test-travis

> static-server@3.0.0 test-travis /home/travis/build/bluzi/static-server
> istanbul cover node_modules/mocha/bin/_mocha --report lcovonly

=============================================================================
Writing coverage object [/home/travis/build/bluzi/static-server/coverage/coverage.json]
Writing coverage reports at [/home/travis/build/bluzi/static-server/coverage]
=============================================================================

=============================== Coverage summary ===============================
Statements   : 16.59% ( 37/223 )
Branches     : 0% ( 0/126 )
Functions    : 0% ( 0/26 )
Lines        : 16.67% ( 37/222 )
================================================================================
/home/travis/build/bluzi/static-server/server.js:9
__cov_WIPUClHv8uANVnHfRm5cnA.s['1']++;const DEFAULT_INDEX='index.html';__cov_WIPUClHv8uANVnHfRm5cnA.s['2']++;const HTTP_STATUS_OK=200;__cov_WIPUClHv8uANVnHfRm5cnA.s['3']++;const HTTP_STATUS_PARTIAL_CONTENT=206;__cov_WIPUClHv8uANVnHfRm5cnA.s['4']++;const HTTP_STATUS_NOT_MODIFIED=304;__cov_WIPUClHv8uANVnHfRm5cnA.s['5']++;const HTTP_STATUS_ERR=500;__cov_WIPUClHv8uANVnHfRm5cnA.s['6']++;const HTTP_STATUS_BAD_REQUEST=400;__cov_WIPUClHv8uANVnHfRm5cnA.s['7']++;const HTTP_STATUS_FORBIDDEN=403;__cov_WIPUClHv8uANVnHfRm5cnA.s['8']++;const HTTP_STATUS_NOT_FOUND=404;__cov_WIPUClHv8uANVnHfRm5cnA.s['9']++;const HTTP_STATUS_INVALID_METHOD=405;__cov_WIPUClHv8uANVnHfRm5cnA.s['10']++;const HTTP_STATUS_REQUEST_RANGE_NOT_SATISFIABLE=416;__cov_WIPUClHv8uANVnHfRm5cnA.s['11']++;const VALID_HTTP_METHODS=['GET','HEAD'];__cov_WIPUClHv8uANVnHfRm5cnA.s['12']++;const RANGE_REQUEST_HEADER_TEST=/^bytes=/;__cov_WIPUClHv8uANVnHfRm5cnA.s['13']++;const RANGE_REQUEST_HEADER_PATTERN=/\d*-\d*/g;_

Error: test error
    at Object.<anonymous> (/home/travis/build/bluzi/static-server/server.js:9:1844)
    at Module._compile (module.js:409:26)
    at Object.Module._extensions.(anonymous function) [as .js] (/home/travis/build/bluzi/static-server/node_modules/istanbul/lib/hook.js:107:24)
    at Module.load (module.js:343:32)
    at Function.Module._load (module.js:300:12)
    at Module.require (module.js:353:17)
    at require (internal/module.js:12:17)
    at Suite.<anonymous> (/home/travis/build/bluzi/static-server/test/server.test.js:8:16)
    at Object.create (/home/travis/build/bluzi/static-server/node_modules/mocha/lib/interfaces/common.js:112:19)
    at context.describe.context.context (/home/travis/build/bluzi/static-server/node_modules/mocha/lib/interfaces/bdd.js:44:27)
    at Object.<anonymous> (/home/travis/build/bluzi/static-server/test/server.test.js:2:1)
    at Module._compile (module.js:409:26)
    at Object.Module._extensions..js (module.js:416:10)
    at Object.Module._extensions.(anonymous function) [as .js] (/home/travis/build/bluzi/static-server/node_modules/istanbul/lib/hook.js:109:37)
    at Module.load (module.js:343:32)
    at Function.Module._load (module.js:300:12)
    at Module.require (module.js:353:17)
    at require (internal/module.js:12:17)
    at /home/travis/build/bluzi/static-server/node_modules/mocha/lib/mocha.js:231:27
    at Array.forEach (native)
    at Mocha.loadFiles (/home/travis/build/bluzi/static-server/node_modules/mocha/lib/mocha.js:228:14)
    at Mocha.run (/home/travis/build/bluzi/static-server/node_modules/mocha/lib/mocha.js:514:10)
    at Object.<anonymous> (/home/travis/build/bluzi/static-server/node_modules/mocha/bin/_mocha:484:18)
    at Module._compile (module.js:409:26)
    at Object.Module._extensions..js (module.js:416:10)
    at Object.Module._extensions.(anonymous function) [as .js] (/home/travis/build/bluzi/static-server/node_modules/istanbul/lib/hook.js:109:37)
    at Module.load (module.js:343:32)
    at Function.Module._load (module.js:300:12)
    at Function.Module.runMain (module.js:441:10)
    at runFn (/home/travis/build/bluzi/static-server/node_modules/istanbul/lib/command/common/run-with-cover.js:122:16)
    at /home/travis/build/bluzi/static-server/node_modules/istanbul/lib/command/common/run-with-cover.js:251:17
    at /home/travis/build/bluzi/static-server/node_modules/istanbul/lib/util/file-matcher.js:68:16
    at /home/travis/build/bluzi/static-server/node_modules/istanbul/node_modules/async/lib/async.js:52:16
    at /home/travis/build/bluzi/static-server/node_modules/istanbul/node_modules/async/lib/async.js:361:13
    at /home/travis/build/bluzi/static-server/node_modules/istanbul/node_modules/async/lib/async.js:52:16
    at done (/home/travis/build/bluzi/static-server/node_modules/istanbul/node_modules/async/lib/async.js:246:17)
    at /home/travis/build/bluzi/static-server/node_modules/istanbul/node_modules/async/lib/async.js:44:16
    at /home/travis/build/bluzi/static-server/node_modules/istanbul/node_modules/async/lib/async.js:358:17
    at LOOP (fs.js:1530:14)
    at nextTickCallbackWith0Args (node.js:489:9)
    at process._tickCallback (node.js:418:13)

npm ERR! Linux 4.9.6-040906-generic
npm ERR! argv "/home/travis/.nvm/versions/node/v4.8.6/bin/node" "/home/travis/.nvm/versions/node/v4.8.6/bin/npm" "run-script" "test-travis"
npm ERR! node v4.8.6
npm ERR! npm  v2.15.11
npm ERR! code ELIFECYCLE
npm ERR! static-server@3.0.0 test-travis: `istanbul cover node_modules/mocha/bin/_mocha --report lcovonly`
npm ERR! Exit status 1
npm ERR! 
npm ERR! Failed at the static-server@3.0.0 test-travis script 'istanbul cover node_modules/mocha/bin/_mocha --report lcovonly'.
npm ERR! This is most likely a problem with the static-server package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     istanbul cover node_modules/mocha/bin/_mocha --report lcovonly
npm ERR! You can get information on how to open an issue for this project with:
npm ERR!     npm bugs static-server
npm ERR! Or if that isn't available, you can get their info via:
npm ERR! 
npm ERR!     npm owner ls static-server
npm ERR! There is likely additional logging output above.

npm ERR! Please include the following file with any support request:
npm ERR!     /home/travis/build/bluzi/static-server/npm-debug.log