WPPostTask + Bitmap optims

WPPostTask done (except attaching image to post itself - i meet some
OutOfMemory error, so now optimizing). First step of optimization -
Bitmap resizing for saving stack space in PostCreationActivity and
DraftActivity. Next step will be in reducing image before pushing it to
server.
WPPostTask is done.
Played with Tumblr. No luck.

See TODO in TBPostTask