plist_dict_set_item: insert key/value pair if key not already present
deprecated plist_dict_insert_item in favor of plist_dict_set_item
updated NEWS
cython: Make sure to use plist_dict_set_item() instead of deprecated plist_dict_insert_item()
Merge branch 'master' of https://github.com/libimobiledevice/libplist
Added header include path to account for setting USE_HEADERMAP to NO.
Validated project file with Xcode 5.1. Added dylib version build settings.