MeterInterpreter fake data cleanup

moved pseudo interval data adding from middleware to frontend, as this
is where it is needed. See http://volkszaehler.org/pipermail/volkszaehler-dev/2013-February/002400.html
for full details.
Merge branch 'master' of github.com:jahir/volkszaehler.org
View\JSON: output from and to as integers, not as strings
channel highlighting fixes
fixed unknown variable exception on group deletetion

also removed handling an unset group id, don't know when this could apply
fixed circular group relation checks

- prevent putting group into itself
- use recursion in circular relation check
make string to int conversion work for 32bit php
some fixes:

- channel moving error message fix
- add parent property to each entity
- remove entity from group when moving (drag'n'drop)
- removed channel graph highlighting by row click, will be done differently
Merge pull request #38 from jahir/master

Mal wieder ein paar fixes...