Adding help text to the options that did not have it.

Many of the config options did not have help text set.  This patch
adds text for those.

patchset2 adds 5 skipped options

patchset3 adds a missing underscore before the helptext bracket

patchset4 fixes pep8 errors

patchset5 notes the units (seconds) in sql_retry_interval, as noted
by Flavio Percoco Premoli

patchset6 fixes comments from Alex Meade

Fixes bug: 1162449
Change-Id: Ic75e499456e389df2ec527594bbcd54c0b464ee3
Merge "Adding help text to the options that did not have it."