http_archive patches and patch_arg attributes do not work

[andrii-apexai]

The patches and patch_arg attributes were introduced here: https://github.com/ApexAI/rules_ros/pull/34/files#diff-a57d11525f1a91bf0c99182bf485b3c95542b41dd96172d161658002a8b5e98bR91. However, corresponding fields were not added to the custom http_archive rule implementation, and thus, it does not work.

[andrii-apexai]

Fixed in #36.