Bugfix for #664, relase publish and smartsheets generate optpng errors.
Merge branch 'v1.1' into bugfix/1.1/#664_release_publish_optipng

Conflicts:
	SpriteBuilder/ccBuilder/CCBPublisher.m
	SpriteBuilder/ccBuilder/PublishImageOperation.m
Refactoring for the bugfix #649 branch.
Split a multi class and protocol file into separate files.
Constant added for the intermediate lookup filenames, put into MiscConstants.
Bugfix for github issue #672.
File modifcation date used to test for changes got out of sync after introduction of intermediatefilelookup.plist files.
Changed publishing status update message for spritesheets, now without plist extension for current filename.
Modification dates of directories needed to be ignored to work properly with intermediate filelookups.
Merge pull request #666 from NickyWeber/bugfix/1.1/#664_release_publish_optipng

Bugfix/1.1/#664 release publish optipng
Merge pull request #667 from NickyWeber/refactor/cleanup_#649_psd_filelookup_issue

Refactor/cleanup #649 psd filelookup issue
Merge pull request #674 from NickyWeber/bugfix/#672_always_full_publish

Bugfix for github issue #672.
Package migration: check added if migration is needed at all.
Merge branch 'develop' of https://github.com/apportable/SpriteBuilder into develop
Merge branch 'develop' into feature/#501_4_migration

Conflicts:
	SpriteBuilder/SpriteBuilder.xcodeproj/project.pbxproj