timeshift: reduce the output buffer size

This will help with a potential overflow in the HTSP buffers that causes
glitches in client playback.
bundle: fix memory leak spotted by EricV
capmt: fix invalid use of free()'d data as spotted by EricV
util cron: re-added code I wrote in early EPG days for handling cron tasks

This will be used as a means of managing mux subscription scheduling.
util cron: fix possible DST issue

really not sure this will work, needs testing
tsfile: Added option to allow a fixed UUID for tsfile muxes

This is useful for testing how they work with other parts of the system
subscriptions: fix potential recursion
mpegts: fix potential deadlock on deletion of input source (while streaming)

Noticed this during tsfile shutdown.
mpegts: new feature for scheduling mux tuning events

Could be useful for requesting periodic tuning of mux for EMM harvesting.
Will eventually be used to replace the current OTA EPG scheduling.
api webui: fix stupid mistake in error reporting spotted by EricV
cwc: fix potential leak spotted by EricV, and also bad var init
dvb: remove redundant code spotted by EricV