Rework dynamic metric support
Force the check that determines if a metric should be handled by a certain dynamic tree to traverse the pmns instead of just checking the cluster
This allows 2 things:
-clusters to be shared between dynamic trees
-does not require related trees to have a common prefix
This requires that the dynamic hash be valid at initailization time
All pmdas that use dynamic metrics must now call pmdaTreeRebuildHash
This was previously required only of daemen pmdas. For dso pmdas, some sort of auto rebuild was occurring
Now this is also required for dso pmdas
Added fixes for the linux interrupts and gfs2 pmdas, although I have no way to test the gfs2 pmda