Slightly modified merge of the cancel-support for Akonadi agents by Constantin Berzan,

with the D-Bus interface changes already integrated into the server.

Merged revisions 986718 via svnmerge from 
https://vkrause@svn.kde.org/home/kde/branches/work/akonadi-ports/kdepimlibs

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  r986718 | tmcguire | 2009-06-25 00:30:24 +0200 (Thu, 25 Jun 2009) | 9 lines
  
  Merged revisions 980072 via svnmerge from 
  svn+ssh://tmcguire@svn.kde.org/home/kde/branches/kdepim/soc/kdepimlibs
  
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    r980072 | cberzan | 2009-06-11 07:01:53 +0200 (Thu, 11 Jun 2009) | 2 lines
    
    AgentInstance::abort() support.  I copied kdesupport/akonadi/interfaces/org.freedesktop.Akonadi.Agent.Control.xml to kdepimlibs/akonadi/interfaces for now.  Agents / resources should connect to AgentBase::abortRequested() to implement abortion.
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svn path=/trunk/KDE/kdepimlibs/; revision=1001801