Bump version
Overview of changes:
* Added subcommand level tab completion
Saturnin v0.5.2 brings in long-awaited support for subcommand tab
completion. These are some basic scriptlets; there is space to
improve but they are already helpful.
* bmo-be now creates status overview files
Ideal for conky-like displays, bars and even shell prompts,
bmo_be.sh now keeps two files that can be read to keep brief status
(SXPR).
* Fixed meta.url variable in bmo-mka templates
Saturnin v0.5.1 added app-url parameter, so now we can make use of
it and have the meta.url variable actually contain something.
* Added bmo-menu command to list all menus
* Cleaned up and improved bmo_be.sh, mostly internally
* Smaller updates, cleanups and fixes