add apache license header
[#6218] Get branches and tags directly from SCM

Signed-off-by: Cory Johns <cjohns@slashdotmedia.com>
[#6218] Fixed failing test due to added tag

Signed-off-by: Cory Johns <cjohns@slashdotmedia.com>
[#6218] Deprecated and removed references to cached heads, branches and tags

Signed-off-by: Cory Johns <cjohns@slashdotmedia.com>
[#6218] Added docstring to get_heads/branches/tags explaining why it's not a property

Signed-off-by: Cory Johns <cjohns@slashdotmedia.com>
Merge branch 'cj/6218' of https://git-wip-us.apache.org/repos/asf/incubator-allura into cj/6218
[#6218] Fix tests

Signed-off-by: Tim Van Steenburgh <tvansteenburgh@gmail.com>