refactoring and various cleanup

[bahamas10]

• remove linestream.js and use lstream in npm
• remove use of new Function
• pure javascript dottedLookup function

Performance gains (hard to measure at such low ms times, probably negligible)

https://gist.github.com/bahamas10/3a6516358d86bcef11c5

The real gain is in safety - no evaluation of user supplied data can happen with this method

Tests pass

$ make check test
./tools/jsstyle -o indent=4,doxygen,unparenthesized-return=0,blank-after-start-comment=0,leading-right-paren-ok lib/tabula.js test/basics.test.js test/cases.test.js test/tap4nodeunit.js
Check ok.
./node_modules/.bin/nodeunit test/*.test.js

basics.test.js
✔ exports

cases.test.js
✔ case: array-cell
✔ case: dotted-lookup-sort
✔ case: dotted-lookup
✔ case: no-columns-option
✔ case: obj-columns
✔ case: object-cell
✔ case: simple
✔ case: skip-header
✔ case: sort-simple
✔ manual case: function-cell

OK: 12 assertions (31ms)