Fixed #if line for iOS7. Previous version occurs memory leaking on iOS7, because there wasn't called dispatch_release(imageUpdateSemaphore) and libdispatch.dylib's malloc wasn't released.
Fix Xcode 4 compatibility
GPUImagePicture: don't redraw using CoreGraphics unless you have to

There was support for this but it appeared to have been disabled.
GPUImagePicture: only access image bytes directly if the bitmap byte order and format is compatible with GL

This correct non-redrawing for JPGs from my previous commit, as they are big endian.
Add Podspec file

This will allow people using GPUImage from Cocoapods to:
* Force the latest version of the library at any time with `pod 'GPUImage', :head`.
* Specify a given commit and/or fork to use with `pod 'GPUImage', :git => 'https://github.com/...', :commit => '...`.
Fix 64bit string formatting issues on iOS
Merge pull request #1287 from aburgel/ios_64bit_fixes

Fix 64bit string formatting issues on iOS
Merge pull request #1270 from rivera-ernesto/add_podspec

Add Podspec file to repository
Merge pull request #1267 from karlvr/gpuimagepicture-redraw

GPUImagePicture: don't redraw using CoreGraphics unless you have to
Merge pull request #1263 from rivera-ernesto/fix_xcode4_compatibility

Fix Xcode 4 compatibility
Merge pull request #1231 from mtfrctl/external

Fixed #if line for iOS7. Previous version occurs memory leaking on iOS7,...
Fixed the MultiViewFilterExample on the Mac side.
Removed a divide-by-zero error in the soft light blend, caused by accounting for premultiplied alpha.
Fixes infinite loops when call endProcess by adding a flag to check if the filter has already started the end process
GPUImagePicture: check that the memory layout is valid for using the CGImage directly in GL

This corrects the fault introduced by my previous commit enabling CGImages to be used directly in GL.
Merge pull request #1298 from karlvr/gpuimagepicture-redraw2

GPUImagePicture: check that the memory layout is valid
Merge pull request #1295 from achambers16/fix-endprocess-loop

Fix infinite loops related to endProcess on GPUImageFilter