Merge branches 'dev' and 'master' of https://github.com/gabrielemariotti/cardslib into dev2
Lib: updated com.jakewharton.sdkmanager to 0.12
Lib-extra: updated com.nhaarman.listviewanimations to 3.0
Lib-extra: updated the drag and drop list using com.nhaarman.listviewanimations 3.0.
Fixed #219 , #252 and ma be the #235.
Demo-extra: updated all dependencies to last releases
Demo-extras: fixed repackaging in sticky list lib
Demo-extras: updated the drag and drop example
Updated doc
Clean up all gradle scripts.
Switched to the new standard com.android.application, com.android.library.
Removed all + wildcards.
Updated demo to support library 20.
LIB: Added a method to add sectioned cards dinamically. Updated the doc. #262
updated doc for header
LIB: Add ability to restrict card swipe direction. #233.
Updated the doc.
LIB: Added the ability to expand and collapse the card with a longClick and in programmatic way. Redesigned the expand/collapse action code.
Added a demo example, and updated doc.
Merge remote-tracking branch 'origin/dev' into native

Conflicts:
	demo/extras/build.gradle
	demo/stock/build.gradle
	library/src/main/java/it/gmariotti/cardslib/library/internal/CardArrayAdapter.java
Merged with dev