Autoadjust label text size for NIFormCells
Added minimum font size …

… of 10.0 to NIFormElementCell's textLabel and
NITextInputFormElementCell's textField
Merge pull request #246 from Shukuyen/formcells

Autoadjust label text size for NIFormCells
Update Namespace headers.
[models] Clean up implicit type conversions.
Add extern "C" macros for C-style functions to avoid linker errors when building with .mm files.
Add ARC support checks to the entire codebase.

It appears that people have been adding Nimbus to non-ARC projects
and experiencing memory leaks.
[core] Add NIFrameOfCenteredViewWithinView to the core.
[core] Delete NIBlocks.h.

These blocks were only being used by the operations, so I've squashed
them into NIOperations.
[core] Remove isWhitespaceAndNewlines method from NSString category and add NIIsStringWithWhitespaceAndNewlines in its place.
[core] Move NSData md5 and sha1 hashes out to C-style functions. Delete NSData category.
[core] Delete UIView+NimbusCore category.
Remove NSData category from the demo apps.
[attributedlabel] Cast enum to an int in alignmentFromUITextAlignment: to avoid warnings about case values not being in the enumerated type.

Closes #249.
Remove dead files from the Catalog sample app.
[pagingscrollview] Fix misc compiler warnings on stricter compiler settings.
[pagingscrollview] Don't inform the delegate of page changes when page changes have been explicitly requested.
[models] Allow the radio group controller to be presented in different ways via the delegate.
[models] Add support to NITableViewActions for attaching actions to classes of objects.
[models] Fix build errors on older versions of Xcode.