Merge branch 'release/1.0.0dev2' into develop
README: Remove XenServer RRD datasource from TODO.
Remove unused GNUmakefile.
Sort component tree in a reasonable way.
Add event collection for XenServer messages.
Add better priority -> severity mapping.
Globally change XAPI to XenAPI.

Based on feedback from John Else in #xen-api on freenode. The API is
called XenAPI. XAPI is the name of the daemon that supports it.
Graph definition tweaking.
Convert full modeling to use xenapi.events.
Working incremental modeling!
Merge branch 'feature/incremental_modeling' into develop
Require PythonCollector>=1.1 for modeling support.
First draft of impact diagram.
Internal impact tests and adapters.
Merge branch 'feature/impact' into develop
README: Update TODOs.
Remove unused XenAPI module.
Monkeypatch ApplyDataMap for incremental model.
Version 1.0.0dev2 -> 1.0.0dev3.
Add icons.