Fixed bug #1136964.
1. Added 3 ini functions to support MultiStrOpt:
Function "iniset_multiline config-file section option value1 value2
value3 ..." sets a MultiStrOpt option in an ini file.
Function "iniget_multiline config-file section option" gets the
MultiStrOpt option values.
Function "iniadd config-file section option value1 value2 value3..."
appends an option without relacing the old values, which would result
the option to be MultiStrOpt.
2. Modified the nova configuation to correctly enable notification for
ceilometer.
Change-Id: I1c27db1a6e58b35bc4428e761f40627988f69e37