move `apple-touch-icon-precomposed` into `images/touch`

as the other touch icons are there.
Output some error when require-dir tasks fails

It could be useful to see the results of the require tasks especially if there is an error.
Merge pull request #426 from alexanderchan/patch-1

Output some error when require-dir tasks fails
Fixes #441 - add custom logPrefix for BrowserSync
gulpfile - add `logPrefix` to the other browserSync instance

and single-quotes
Update dependencies
Merge pull request #455 from google/update-deps

Update dependencies
bump dependencies

to fix a bug in a deep down dependency when used in node 0.11.0
gulpfile - comment out the task loading by default

so it doesn't log an error when there's no `task` folder
Add missing space before commented out code.
Merge pull request #411 from google/move-ios-touch-icon

move apple-touch-icon-precomposed.png into `images/touch`
Fixes #82 - use LibSass instead of Ruby Sass
Add back precision
Bump deps
Merge pull request #484 from google/libsass

Fixes #82 - use LibSass instead of Ruby Sass