Use WinJS functionality to resize image instead of File plugin functionality
Removes File plugin dependency from windows8 code.
Docs updated with some default values

close #35
Remove iOS doc reference to non-existing navigator.fileMgr API

close #13
Prevent NPE on processResiultFromGallery when intent comes null

close #22
ios: Delete postImage (dead code)
CB-6875 android: Handle exception when SDCard is not mounted

close #29
Tweak docs to not use []'s for optional arg since that's JS array notation

close #21
CB-7071 android: Fix callback firing before CROP intent is sent when allowEdit=true