This updates a few of our core patch-related objects in preparation for

new patching support.
PatchAuthor now stores the full name as full_name, rather than

fullname. There's a legacy, deprecated alias to support the old name.

It also supports equality checks.
PatchResult has a new patch_range attribute shows the range within a

set of patches that this result applies to. Note that one patch may

cover more than slot in the range (if squashed by a patcher).
Patch, PatchAuthor, and PatchResult all gained a __repr__()

method to aid in debugging.

Unit tests pass.
Used these with in-progress code.