t2 restore: make api testable, match promise interface used throughout.

Closes gh-493

- update-fetch.js made testable (TODO: more tests to be written)
- restore: adds -f to skip device id check
- restore: simplified controller handler
- consolidate contents of "flash.js" into "restore.js"
- restore.js: eliminate async, uses promises
- restore.js: substantial tests, but still lacking coverage in a few areas, this can be done in a follow up
- updates to jshintrc and bootstrap.js

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>

bin/tessel-2.js

@@ -140,11 +140,16 @@ parser.command('provision')
   })
   .help('Authorize your computer to control the USB-connected Tessel');
 
-parser.command('restore')
+makeCommand('restore')
   .callback(options => {
     log.level(options.loglevel);
     callControllerWith('restoreTessel', options);
   })
+  .option('force', {
+    abbr: 'f',
+    flag: true,
+    help: 'Skip the Device ID check and restore. Including this flag is not recommended, but may be necessary if Tessel memory device contents are corrupt.'
+  })
   .help('Restore your Tessel by installing the factory version of OpenWrt.');
 
 makeCommand('restart')

lib/controller.js

@@ -562,13 +562,7 @@ controller.restoreTessel = function(opts) {
   opts.altSetting = 1;
   return controller.get(opts).then((tessel) => {
     return new Promise((resolve, reject) => {
-      tessel.restore(opts)
-        .then((result) => {
-          resolve(result);
-        })
-        .catch((err) => {
-          reject(err);
-        });
+      return tessel.restore(opts).then(resolve).catch(reject);
     });
   });
 };