In About Dialog, display default branch name/SHA in case it cannot be determined
Add measurement for caching project content.
Add experimental multi-browser LiveDevelopment

Brings in new LiveDevelopment implementation incubated at
njx/brackets-livedev2 which allows running on multiple browsers.
Add node modules for launching default browser
Add node modules for ws transport implementation
fix jshint findings
fix JSLint (no jshint) issues in tests now
fix jshint issues
Semi-fix for bug #10013 (CSS Quick Edit provider does not respond if project
contians any non-UTF8 CSS/LESS/SCSS files) - Silently ignore files that can't
be read, and continue the search anyway (warning logged to console, but no
user-visible error shown). Similar to what we've always done for Find in Files.

With unit test, and matching test for the pre-existing same behavior in Find
in Files. Also clean up dated use of waitsFor() in the CSSUtils test spec.
fix typo DocumentRelated
Merge remote-tracking branch 'upstream/master' into multibrowser-livedev
minimum space units should be 1
Remove unused vars, fix typo in test suite name, leave error object
inspectable in console.warn() call.
remove array from event arguments
add methods to align it with LiveDevelopment API
Merge remote-tracking branch 'upstream/master' into multibrowser-livedev
Ensure that the baseDir for createNewItem is within the project.

This is a fix for #9910.
Merge remote-tracking branch 'origin/master' into randy/issue-9899
Fix bug #9966 ([CEF 2171] JSLint doesn't work) - Switch to a private fork
of JSLint with the bug fix cherry-picked in so we're not stuck upgrading to
a much newer JSLint which has the fix but is significantly stricter / less
configurable.

Note: you must run `git submodule sync` in order for the submodule URI
change to take effect.
Merge pull request #10063 from adobe/randy/issue-9899

Minimum space units should be 1