Fixes the tag regex for codeship

Author: avirshup

codeship-steps.yml

@@ -15,7 +15,7 @@
        name: check_pyversion
      - command: ./scripts/deploy.sh
        name: pypi_deploy
-  # tests for semantic versions
-  tag: '^(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(-(0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(\.(0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*)?(\+[0-9a-zA-Z-]+(\.[0-9a-zA-Z-]+)*)?$'
+  # tests for (a subset of) PEP440 versions
+  tag: '^(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)((a|rc|b)(0|[1-9]\d*))?$'