Stop timeshifting dialog made optional via Configuration
Add "for" in "ask confirmation when stopping timeshift" config option

As suggested by Holzi, thanks!
Added option for Confirmation when stopping time shift in GUI TV settings.
Note: Skin file "settings_tv.xml" needs update for all three MP skins (Default, DefaultWide and Titan) with checkbutton

Changes:
New GUICheckButton with id 29
New Language string with id 300228
Merge branch 'master' into FEAT_Optional_stop_live_TV_dialog

Conflicts:
	mediaportal/Configuration/Sections/TVClient.cs
Update skin files for GUI Option.

Credits to skinners:
- Titan skin file by ncoH
- Default and DefaultWide skin files by catavolt
Move "ask confirmation when stopping timeshift" option to notifications tab

Also rename the tab from Notifier to Notifications.
Merge branch 'master' into FEAT_Optional_stop_live_TV_dialog

Conflicts:
	mediaportal/Configuration/Sections/TVClient.cs
Merge branch 'FEAT_Optional_stop_live_TV_dialog'