Add support for new Alpine's pipelines

Fixes #30 (closed)

It contains a considerable amount of refactoring, so some testing would be helpful. There might be more work to do, like moving parse_git_origin to origin. But I don't want to get carried away even more

docs/mrhlpr/mrhlpr.rst

@@ -44,6 +44,14 @@ mrhlpr.mrdb module
    :undoc-members:
    :show-inheritance:
 
+mrhlpr.origin module
+--------------------
+
+.. automodule:: mrhlpr.origin
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 mrhlpr.pipeline module
 ----------------------