Bug 917144 - remove some apps to reduce image size

remove apps list below to reduce image size for engineering build:
- cubevid
- testpermission
- image-uploader
- crystalskull
- test-ime
- tests-sensors
Merge pull request #12384 from yurenju/reduce-size

Bug 917144 - remove some apps to reduce image size
Bug 885713 - propose a "make hint" that would use jshint instead of gjslint

This adds
* a default .jshintrc configuration file
* a `make hint` launcher
* a way to launch the linters (including the old lint linter) for a specific app
  only.
* you can also use another jshint configuration file
Follow-ups:

* use npm to install jshint
* simplify the jshint command line, now that I checked that current jshint does
  not choke on our files
* use .jshintignore file as main exclude file, from both gjslint and jshint
Follow-ups:

* fix paste call in MacOS X
* pre-commit change
* remove node_modules from .PHONY because I don't want to always run this,
  especially when I'm offline
* remove the node_modules directory in really_clean
Follow-ups:

* use real files instead of phony targets for node modules and git hooks
* don't execute make lint in the commit hook if we have no js files
* make make quieter in the commit hook
* use target-only variables for the lint target