Proper handling of @import directive inside a file read using pkg_resources
Proper handling of @import directive inside a file read using pkg_resources

load_definitions() takes a new parameter to indicate if the file was loaded
from as a pkg_resource. In that case, related files will be opened in the
same way.

See #68 and ufo-kit/concert#94

tiagocoutinho/pint,tiagocoutinho/pint,dmwelch/pint