Gradle plugin for setting up WordPress libraries

Potential way to manage libraries via artifacts or from source.
Cleaning up dependency location
Blog preview now shows domain if name is empty
Workaround for Android 4.4.3 bug that caused rotate animation to fade the like icon
style fixes
fix #1550: check for null context in ProcessAttachmentsTask.doInBackground
pass context parameter to ProcessAttachmentsTask constructor
null check for context in addMedia
use emailchecker 0.3
Merge pull request #1605 from wordpress-mobile/issue/1550-npe-ImageHelper.getImageSize

fix #1550 npe image helper.get image size
Merge pull request #1607 from wordpress-mobile/issue/1606-emailchecker-0.3

fix #1606: use emailchecker 0.3
Moving gradle plugin to own project
Merge branch 'feature/modularization' into issue/1575-local-dependency-setup
Merge remote-tracking branch 'origin/issue/extract-wpcom-rest' into issue/1575-local-dependency-setup

Conflicts:
	WordPress/build.gradle
	settings.gradle
Using 1.1.0 of gradle plugin
fix #1588: check for activity destroyed before opening a post
Merge pull request #1615 from wordpress-mobile/issue/1588-ise-activity-destroyed-postsactivity

fix #1588: check for activity destroyed before opening a post
Merge branch 'feature/modularization' into issue/1575-local-dependency-setup
add libs/ to gitignore and remove old dependency directories
add wpcomrest as a dependency since some WPAndroid parts is still directly dependent on it