Auto reajust scrollview subviews y value

[andrefmsilva]

with this we can add views direct in xib and they will reajust when image is added

[cyndibaby905]

Hi @Zasuk , thanks for your contribution:) But I have to say may be I won't accept this pull request. Yes, when using TwitterCover, the content of UIScrollView should begin at CGPointMake(0,CHTwitterCoverViewHeight) instead of CGPointZero, since the area CGRectMake(0,0,self.width,CHTwitterCoverViewHeight) is reserved for TwitterCover, your code highlighted this, which is good. But I think this adjustment should be outside UIScrollView itself, since addSubView can happen in anywhere. May be UIViewController is a better place to do this adjustment.