help: don't try to render a section on sub-topics This patch subtly changes the behavior of the parsing of "X.Y" values to not set the "section" variable when rendering a known sub-topic. Previously, "section" would be the same as the sub-topic name. This required the sub-topic RST to have a section named the same as the sub-topic name. When I made this change, the descriptions from help.internalstable started being rendered in command line output. This didn't look correct to me, as it didn't match the formatting of main help pages. I corrected this by moving the top section to help.internalstable and changing the section levels of all the "internals" topics. The end result is that "internals" topics now match the rendering of main topics on both the CLI and HTML. And, "internals" topics no longer require a main section matching the name of the topic.

branchmap: remove extra indent This clean up the rest of the previous changeset.

branchmap: simplify error handlind when writing rev branch cache Now that we have a general try except, we can move the error handling from the individual writes in it. Code will be reindented in the next changeset to help this on readability.

branchmap: acquires lock before writting the rev branch cache We now attempt to acquire a lock and write the branch cache within that lock. This would prevent cache corruption when multiple processes try to write the cache at the same time.