Migrate sencha touch lib to newest version

Adapt makefile to use the latest version of the sencha touch library
This fixes some bugs, which includes some really annoying ones like
the inability to scroll on mobile chrome (and other browsers).
Sencha touch can be obtained from https://www.sencha.com/legal/GPL/Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

www/touch/Makefile

 include ../../defines.mk
 
-TOUCHDIR=touch-2.3.1
-TOUCHSRC=sencha-touch-2.3.1a-gpl.zip
+TOUCHDIR=touch-2.4.2
+TOUCHSRC=sencha-touch-2.4.2-gpl.zip
 
 TOUCHDATA = 					\
 	${TOUCHDIR}/sencha-touch-all.js		\