Update podspec for 1.2.0.
Update podspec for 1.2.0.

kishikawakatsumi/PEPhotoCropEditor,chicisimo/PEPhotoCropEditor,BluechipSystems/PEPhotoCropEditor,wonderkiln/PEPhotoCropEditor,kiwamunet/PEPhotoCropEditor,imjerrybao/PEPhotoCropEditor,KaterinaPetrova/PEPhotoCropEditor,david90/PEPhotoCropEditor,mr-v/PEPhotoCropEditor,yangmie/PEPhotoCropEditor,Adorkable-forkable/PEPhotoCropEditor