teletext: fix extractPTS

copy extract_pts implementation from subtitle.cpp
reducing the number of bitshifts, and fixing the
LSB offset
(see 3b24f0d476f16733823852e3778360a8276d9b59)

NOTE: the 7 least significant PTS bits account
for 1.41ms, so the LSB offset bug would not have
had a noticable effect on teletext subtitle timing
Make latest changes to NumberZap backwards compatible with some skins

And remove in addition some absolute code
Revert "Solve typo in skin_default.xml"

This reverts commit 30f6a33575e4881aa111e78fbb0b16738b09fce2.

As backwards compatibility is now added in InfobarGenerics
Revert "Adjust default skin to NumberZap changes"

This reverts commit e798ea507329a79d0e8fedf363951e9cf12c9fdb.

As backwards compatibility is now added in InfobarGenerics
Rename self.field to self.numberString in NumberZap

As this is a better descriptive variable. This is pure cosmetic
Add front display for GMEPG for VUDUO/ET8K/ET10K
Do not startup to standby when the UI is restarted

Thanks IMS for reporting this
Small optimalization for my previous commit

As misc.RestartUI config needs only to be saved in Standby.py when it is
set to true
Merge remote-tracking branch 'pli/master', skip some stuff.