[Pidgin] #10029: Support XDG dir structure

[Pidgin]

#10029: Support XDG dir structure
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 Reporter:  salinasv   |       Owner:  EionRobb
     Type:  task       |      Status:  new
Milestone:  3.0.0      |   Component:  unclassified
  Version:             |  Resolution:
 Keywords:  XDG 3.0.0  |
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Comment (by elrond):

 I think, it is a good idea to start moving some files over. It does not
 hurt to keep some in .purple until it is known where to put the things.

 From looking at the wiki, the most obvious ones are:

 || certificates/    || * || XDG_DATA   ||
 || icons/           || * || XDG_CACHE  ||
 || logs/            || * || XDG_DATA   ||
 || xmpp-caps.xml    || * || ? XDG_CACHE ||
 || pounces.xml      || * || ? XDG_DATA ||

 The last two entries are my personal guess deviating from the wiki.

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Ticket URL: <https://developer.pidgin.im/ticket/10029#comment:14>
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