Merge remote-tracking branch 'upstream/develop' into navigationDrawer_update

Merge remote-tracking branch 'upstream/develop' into navigationDrawer_update

# Conflicts:
#	gradle/wrapper/gradle-wrapper.properties
#	owncloud-android-library
#	res/layout-land/account_setup.xml
#	res/layout/account_setup.xml
#	res/layout/list_item.xml
#	res/layout/uploader_list_item_layout.xml
#	res/menu/main_menu.xml
#	res/values/colors.xml
#	res/values/strings.xml
#	src/com/owncloud/android/MainApp.java
#	src/com/owncloud/android/operations/SynchronizeFolderOperation.java
#	src/com/owncloud/android/ui/activity/FileDisplayActivity.java
#	src/com/owncloud/android/ui/activity/Preferences.java
#	src/com/owncloud/android/ui/activity/Uploader.java
#	src/com/owncloud/android/ui/adapter/FileListListAdapter.java
#	src/com/owncloud/android/ui/adapter/LocalFileListAdapter.java
#	src/com/owncloud/android/ui/fragment/OCFileListFragment.java
#	src/com/owncloud/android/ui/preview/PreviewImagePagerAdapter.java
#	src/com/owncloud/android/utils/BitmapUtils.java