Don't optimize images on serve

(#180)[http://github.com/google/web-starter-kit/issues/180]
Inject CSS styles

Looks like styles are reloading the whole browser. This should inject them without a full reload. I tested with 10 simultaneous CSS file changes, seems to work well.
Handle error event generated by jshint fail reporter

Closes #194
typo fix
Merge pull request #195 from mrmlnc/master

typo fix
Merge pull request #187 from robwierzbowski/patch-3

Inject CSS styles
Remove reload from the images task
Merge pull request #182 from matheusazzi/patch-2

No longer optimize images on serve.