Add a bootstrap repo file stage

Allow for fetching additional dependencies for openstack
by allowing for fetching of arbitary repo files during
the bootstrap process.

Add an initial example that allows for fetching the RDO
repo file (which provides quite a few of the same python
dependencies that anvil will build automatically if it
can not find them itself).

Change-Id: Ia51adf017d398863432ecb9d218e163235039488
Sort the downloaded dir

To show the downloaded files in sorted order sort
the output of the dir listing instead of leaving
it unsorted.

Change-Id: Iac85ee4e2519995ea5e7f6d6f6740846b4b6cd36
Adjust == conflicts

When a version is found that is the same as the ==
version the only way that can not be a conflict is
if the operator is == and nothing else (like <= or
>= or !=...)

Change-Id: I2a2f0b6dace7a62216a0f4fb4d68a4cf5be8c0f7
Merge "Sort the downloaded dir"
Merge "Add a bootstrap repo file stage"