Add parameter support when executing queries
Remove conflicts for compatibility with older postgres installs
Remove buffers_backend_fsync for compatibility
Don't log false-y values
Override publish method to skip falsey or 0 values
Set 'postgres' as the default database if none is specified
set unit to B by default in doc string
Do not use broken abs mode in threaded interval tasks.

Threading and interval tasks do not mix with abs mode, as the next
job is scheduled immediately after spawning the thread for the current
thread.  Not only does it not make sense (a job running significant
time is scheduled too often), it is actually harmful (a long running
job will cause the calculated delay to be zero, which creates a tight
loop that spawns threads until the system runs out of process slots,
essentially making diamond a temporary fork bomb).
Comment fix.
Merge pull request #368 from huoxy/master

fix func doc
Fixes #367, this adds in NagiosPerfdataCollector.
Merge pull request #369 from huoxy/set-unit-to-B-by-default-in-doc-string

set unit to B by default in doc string
Merge pull request #372 from lambdafu/master

Do not use abs mode for threaded or forked interval tasks.
PEP8
Doc updates
Changed elasticsearch collector not to blow up if CPU, memory or file stats are not present in the JSON response (e.g. due to access rights of user running elastic)
Used _add_metric wherever applicable in elasticsearch collector
Final use of _add_object wherever appropriate in elasticsearch collector
Fix a stacktrace when the directory does not exist
Disable the NagiosPrefData Collector by default