make bookmark local
flip equals to avoid NPE
stop processing intent if url is empty
removed null check for description

Description is null anyway so this condition is not needed.
extracted service call to separate method
moved requestAccount to SaveReadLaterBookmark
SaveReadLaterBookmark no longer needs to depend on FragmentBaseActivity
account manager can be local
extracted bookmark saving to separate method
fixed log message
Merge pull request #20 from delor/fix_save_read_later

Fix save to Read Later