shelve: rename method for data write/read There are no user of this code nor any code related to obsshelve in the extensions right now, so we rename the function before using them. Note: The shelvedfile looks a bit strange. We should probably refactor it, however, this is an adventure for another series.

shelve: move createcmd next to _docreatecmd It is simpler not to have to jump around the file all the time.

minirst: filter blocks by full path to section

minirst: mark getsections() as an internal helper

help: rewrite parsing of help topic to not drop section name with dots A subtopic is no longer lowercased since it should be considered a part of a topic path, not a section filter.

test-help: add tests showing that sections can't be filtered by dotted name