changed: Implement ChapterOrBigStep-actions and make previous BigStep-actions without chapter seeking

Conflicts:
	xbmc/cores/amlplayer/AMLPlayer.cpp
	xbmc/cores/dvdplayer/DVDPlayer.cpp
	xbmc/cores/omxplayer/OMXPlayer.cpp
	xbmc/cores/omxplayer/OMXPlayer.h
	xbmc/guilib/Key.h
Revert "Optionally allow caching for all network streams, including those on LAN (via new advanced setting 'alwaysforcebuffer')"

This reverts commit 821e28adbf2457e89dcf1871ab115e6f248d0306.
Revert "Use advancedsetting to speed up ReadRate in players"

This reverts commit ee46c3772b0753dfe7c0bd77b9a6d66f5f8a0a7b.

Conflicts:
	xbmc/settings/AdvancedSettings.cpp
	xbmc/settings/AdvancedSettings.h