iptv: fix service config saving

Fixes #2013
url: minor correction based on suggestion from MinGyoon

Fixes #2012
muxer dvr: fix configuration passing to reduce potential for error

This should fix #2015
Merge remote-tracking branch 'upstream/master'

Conflicts:
	src/dvr/dvr_rec.c
	src/muxer.h
	src/webui/extjs.c
	src/webui/webui.c
Refactor of dvr config pages; add of user options for file/directory permissions throughout