Updated README

Changed capitalization on CocoaPods instructions.
Renamed delegate method and fixed animation glitch

Delegate method now passes ASProgressPopUpView as a parameter.
Animation now starts from the correct point when setting
‘alwaysShowPopUpView’ to YES.
Remove animation only if it has completed
Precalculate popUpView size when setting delegate

Keeps the popUpView size consistent as it moves.
Implemented ASProgressPopUpViewDataSource

Moved ‘progressView:stringForProgress:’ to dataSource protocol.
Implement the dataSource protocol to supply custom string values to the
popUpView label. The popUpView size is calculated in advance to stay
consistent - though you can opt out of this if needed.
Set _textLayer frame to rect integral

Ensures pixel alignment for crisp text
Reset frame after adjusting layer anchorPoint
Set popUpView frame to rect integral

Frame should be set before calculating arrowOffset to get an accurate
result.
Call 'positionAndUpdatePopUpView' before hiding popUpView
'calculatePopUpViewSize' now adapts considers dataSource

If there’s a dataSource then calculate the popUpView size based upon
it’s values, otherwise use the default string ‘100%’.
Only call 'positionAndUpdatePopUpView' when needed
Added extra progress view example
Handle nil from dataSource progressView:stringForProgress:

Show default percentage value if nil is returned from dataSource.
Changed example progressView
Merge branch 'custom_label'
Version 0.5
Updated ‘features’ in README
Updated README with more info
changing bounds