Fix for iOS8 UIActivityViewController Popover Presentation

Tapping the Action button in iPad on iOS will generate a crash. This is because UIActivityViewControllers are presented in a UIPopoverController in iOS8. So, they need to be anchored. Added code to access the popover to set the anchor point.

See: http://stackoverflow.com/questions/25644054/uiactivityviewcontroller-crashing-on-ios8-ipads
Updated SDWebImage and updated projects for Xcode 6

Fixes #299
Merge branch 'develop' of github.com:mwaterfall/MWPhotoBrowser
Merge pull request #300 from DeepFriedTwinkie/patch-1

Fix for iOS8 UIActivityViewController Popover Presentation on iPad
Updated podspec and bumped to 1.4.1

Closes #303
Fixed Issue #304 "Zooming issue in iOS 8"

This commit resolves the issue new to iOS 8 that causes the MWZoomingScrollView to jump to the top or left before animating the zoom effect.
The result of this fix is an elimination of the jumpy zooming behavior, and a return to the smooth zooming animation behavior seen before iOS 8.
This fix has been tested on both iOS 7 & iOS 8.

The cause seems to be a change to the way the layoutSubviews is called in iOS 8. The solution was to force the MWZoomingScrollView to layout its subViews in the scrollViewDidZoom method of the delegate.

See this thread for more information: http://stackoverflow.com/questions/25852883/uiscrollview-zoom-out-issue-ios-8-gm/26091731
Merge pull request #315 from dfmuir/master

Fixed Issue #304 "Zooming issue in iOS 8"
Merge branch 'master' of https://github.com/mwaterfall/MWPhotoBrowser

Conflicts:
	MWPhotoBrowser.podspec
	MWPhotoBrowser.xcworkspace/xcshareddata/MWPhotoBrowser.xccheckout
	MWPhotoBrowser/MWPhotoBrowser.xcodeproj/project.pbxproj