more sensor consolidation and cleanups, replace php closing statements by EOF comment

git-svn-id: http://observium.org/svn/observer/trunk@4489 61d68cd4-352d-0410-923a-c4978735b2b8
consolidate and clean up deltaups, also fix battery current being reported as battery frequency

git-svn-id: http://observium.org/svn/observer/trunk@4490 61d68cd4-352d-0410-923a-c4978735b2b8
consolidate and deduplicate raritan sensor code

git-svn-id: http://observium.org/svn/observer/trunk@4491 61d68cd4-352d-0410-923a-c4978735b2b8