Avoid compiling xcassets in some cases

Added a condition to avoid compiling xcassets when WRAPPER_EXTENSION
is undefined, as it would be in the case of static libraries. This prevents
trying to copy the compiled files to a directory that does not exist.
[CHANGELOG]
Merge pull request #1521 from nmccann/feature/fix_resources_script

Avoid compiling xcassets in some cases
Sync integration spec fixtures.
Moving private methods only used by spec lint into its class
[Bundle] update
[CopyResourcesScript] FIX xcassets not compatible with Xcode < 5.0.0.
[CHANGELOG] Cleanup.
Merge branch 'michalkonturek-master'
Sync integration spec fixtures.
[CHANGELOG] CLAide plugins enhancement
Corrected wrong output path passed to actool.
Using UNLOCALIZED_RESOURCES_FOLDER_PATH instead of WRAPPER_NAME as output directory for actool.
Added note to CHANGELOG about changed output directory for actool.
[CHANGELOG] Update for Core Bug Fixes
Merge pull request #1553 from leshill/gem_changelog

[CHANGELOG] CLAide plugins enhancement
[CHANGELOG] Add another plugin ticket.
[CHANGELOG] Add note about taking into account we have no stable API.
Merge pull request #1556 from Widgetlabs/fix-actool-wrapper-name

Corrected wrong output path passed to actool for Apps.
Update integration specs.