flip image bug fix #39
Merge pull request #40 from blackm00n/issue_39

flip image bug fix #39
Fixed warnings when compiling in upcoming version of Xcode
Merge pull request #41 from synchromation/master

Fixed warnings when compiling in upcoming version of Xcode
cropToSize: take image orientation into account 

Fixes #43
Fix possible crash

In case of no network didReceiveResponse: was not called and so _imageSource could be a dangling pointer.
Preserving scale for @2x and @3x displays when calculating grayscale
Merge pull request #46 from Sigmapoint/master

Preserving scale for @2x and @3x displays when calculating grayscale