Added build.sh to produce a universal iOS library
Added color filter

Use case: Set all the pixels of an image to a color, for generating
fast background colors.
Add convenience method to GPUImageFilterPipeline to get a UIImage with specific orientation
Fixed the haze and levels filters under iOS 7.0.
Allow matching existing alpha value in color generator filter
Put solid color generator overloads back, improve performance
GLSL fixes
Merge pull request #1024 from jjxtra/master

Solid color generator filter alpha option
Fixed some poorly-named macros that were conflicting with other frameworks.
Remove obsolete flag for appledoc build script
Edge detection filters now have an adjustable strength. Hough line detector is a little cleaner with the use of iOS 6.0 framebuffer reads.
Merge pull request #1035 from masonk/master

Make the Appledoc build again
Merge pull request #997 from cocologics/master

Add convenience method to GPUImageFilterPipeline
Merge pull request #955 from zimuliu/master

Added build.sh script to compile a universal library for iOS
Tweaked the documentation.
If GPUImagePicture is passed an empty image, create a small 2x2 image to prevent a possibly fatal error on CGContextDrawImage

The empty image passed to GPUImagePicture will trigger this error when CGContextDrawImage is called on init::

"<Error>: CGContextDrawImage: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context  and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update."

This should prevent the error altogether.
Fix static analysis warning in that new Xcode
Added GPUImageRawDataOutput and GPUImageRawDataInput to the Mac port with necessary modifications.
GPUImageVideoCamera: make class methods to determine whether front and or back facing cameras exist

The new iPod Touch doesn't have a back camera, so it's useful to determine which cameras exist before initting the GPUImageVideoCamera.

I have left instance methods of the same name so that the property getters still work, there are just class method alternatives now too.
Introduced outputTextureOptions for GPUImageOutput.

This allows to modify the texture settings of a filter to, for example, allow float-typed output textures.