Move ARC feature-check from header file to implementation file

Previously feature-check in iCloud.h was falsely failing in a non-ARC project even when ARC was enabled for iCloud.m.
Remove iCloud.framework built output
Add standard .gitignore file.
Merge pull request #29 from bgfriend0/ARCFeatureCheckFix

Move ARC feature-check from header file to implementation file
Readme Update

Minor correction to Readme documentation. Fixes #32
Bug in file upload

Fixed a bug where [documentsDirectory stringByAppendingPathComponent:]
would be used twice
Merge pull request #41 from criistii/master

Fixed bug in file upload
Merge pull request #30 from bgfriend0/remove_build_output

Remove build output and add standard .gitignore