templater: add separate() template function A pretty common pattern in templates is adding conditional separators like so: {node}{if(bookmarks, " {bookmarks}")}{if(tags, " {tags}")} With this patch, the above can be simplified to: {separate(" ", node, bookmarks, tags)} The function is similar to the already existing join(), but with a few differences: * separate() skips empty arguments * join() expects a single list argument, while separate() expects each item as a separate argument * separate() takes the separator first in order to allow a variable number of arguments after it

bookmarks: jettison bmstore's write() method per deprecation policy

merge with stable

deprecation: gate deprecation warning behind devel configuration Regular users are not supposed to be exposed to the API deprecation warnings. We now only issue them when the developper warnings are enabled.

crecord: update downarrowshiftevent() docstring, remove todo The phrasing is mostly taken from uparrowshiftevent().

crecord: remove things that don't happen in functions from their docstrings Scrolling screen is currently done in a different place. The things that had been described in the docstrings may still happen, but the functions touched by this patch don't do any scrolling, they only set self.currentselecteditem and nothing more.

crecord: remove skipfolded keyword argument from patchnode.previtem() It wasn't used, it wasn't implemented. Probably was a copy-paste bonus from patchnode.nextitem()

crecord: update a copy-pasted comment in downarrowshiftevent()

crecord: drop the version condition for amend The UI is now shipped in core, amend feature is always available.

crecord: add/remove blank lines (coding style)