Adds basic sharing to WordPress for iOS from other iOS apps.

Supports drafting a new post with a title, some content, tags, and a URL to an image that
will appear as a link inserted at the top of the post.
Support for base64 encoded images should coinside with the updated media library feature.
Fixes #299 - Added width/height labels to custom image size fields; compressed screen components so buttons will be visible on 3.5” iPhone.
Tap on custom image size screen to dismiss keyboard (and show potentially hidden controls).
Localized ”Loading…” label on iPad version of WPWebViewController screen.
Localized ”Reply” button on inline comment screen.
Switched on Autoshrink on the app title on the About screen; in Dutch, the title was displayed as ‘WordPress voor i…”
Integrated tap-on-view-to-dismiss-keyboard in existing tappedOnView handler.
Back to original layout.
Update the components’ size and location after the localized button label has been set, on the InlineComposeView.
Fixes #1041 - Display blog url as subtitle in blog list.
Added new WPStyleGuide method for styling cells with a smaller subtitle font.
Added URL subtitle in the blog selection popup as well.
Subclassed WPTableViewCell to WPBlogTableViewCell for blog site cells with url in subtitle.
New WPBlogTableViewCell added to project settings.
Updated version numbers for 4.0 release
Merge branch 'develop' of github.com:wordpress-mobile/WordPress-iOS into feature/sharing
Use existing subtitleFont instead of new tableViewSubtitleFontSmall.
Clarify what's being logged, and don't use pointers for NSUIntegers.
Center Send button properly by shifting 1 pixel to the left.
Merge pull request #1211 from wordpress-mobile/feature/sharing

Feature/sharing