Satconfig: solve issue when using wizard

If use wizzard and screen Satconfig not work button OK. OK button to select the necessary satellites("Press OK to select satellites"). Left/Right to replace it.
http://openpli.org/forums/topic/33955-satconfig-add-new-option/#entry442483
ChoiceList: Only load PNG when key is defined

As suggested here:
http://openpli.org/forums/topic/28532-merge-requests-for-plis-git/page-32#entry441828

Use a format-string instead of concatenation. This allows any printable
object to be used as key name (e.g. numbers) instead of forcing key to be
a string, it's more efficient and it won't crash when key is something else.
Downloader: replace import of urlparser

Not smart to "import" it at each call.
Enable remove services from all bouquets

This allow delete services from sateiiite or all service bouquets

Signed-off-by: littlesat <littlesat99@yahoo.com>
Add option "Network scan" yes/no for Automatic scan

If not, it is much less time to scan.
As suggested by Dima73
http://openpli.org/forums/topic/33955-satconfig-add-new-option/
Merge branch 'master' of git://git.code.sf.net/p/openpli/enigma2