packaging tidbits

[Matthias Clasen]

Quick reminder, there have been some changes in the packaging guidelines
that affect many desktop packages:

- the standard icon cache snipplet has been reworked:
https://fedoraproject.org/wiki/Packaging:ScriptletSnippets#Icon_Cache

- scrollkeeper-update calls are no longer required:
https://fedoraproject.org/wiki/Packaging:ScriptletSnippets#Scrollkeeper

It might be worth cleaning those things up in passing while updating
packages. 


Matthias