mysql cart: simplify user env var check

Eliminate the "`-n`" test for `OPENSHIFT_MYSQL_START_TIMEOUT` (and
...`_STOP_TIMEOUT`) and replace it with the `set -u` safe
`${OPENSHIFT_MYSQL_START_TIMEOUT:-}` expansion
Merge pull request #5816 from dobbymoodge/mysql_cart_tweak

Merged by openshift-bot
Multiple bug fixes:
Bug 1086061 - Should update the description of clean command for oo-admin-ctl-cartridge tool
Bug 1109647 - Loss of alias on SYNOPSIS part for oo-admin-ctl-app
Bug 1065853 - Should prompt warning when leaving source code url blank but add branch/tag during app creation
Bug 1143024 - A setting of ZONES_MIN_PER_GEAR_GROUP=2 with two available zones will always error as though only one zone is available
Bug 1099796 - Should refine the error message when removing a nonexistent global team from file
Merge pull request #5819 from abhgupta/abhgupta-dev

Merged by openshift-bot
<oo-accept-broker> fix up handling of IFS

- IFS handling in oo-accept-broker was causing a false positive when
  reading the broker rails env and parsing the $SCLS variable.
Use domain max_gears when displaying app scaling limits
Merge pull request #5822 from liggitt/domain_scaling_capabilities

Merged by openshift-bot
Merge pull request #5821 from detiber/bz1142200

Merged by openshift-bot
bump_minor_versions for sprint 51
Automatic commit of package [rubygem-openshift-origin-frontend-apachedb] release [0.6.1-1].
Automatic commit of package [rubygem-openshift-origin-node] release [1.31.1-1].
Automatic commit of package [openshift-origin-cartridge-jbosseap] release [2.21.1-1].
Automatic commit of package [openshift-origin-cartridge-jbossews] release [1.29.1-1].
Automatic commit of package [openshift-origin-cartridge-postgresql] release [1.29.2-1].
Automatic commit of package [rubygem-openshift-origin-admin-console] release [1.26.1-1].
Automatic commit of package [rubygem-openshift-origin-frontend-haproxy-sni-proxy] release [0.4.1-1].
Automatic commit of package [openshift-origin-cartridge-mysql] release [1.28.1-1].
Automatic commit of package [rubygem-openshift-origin-routing-activemq] release [0.6.1-1].
Automatic commit of package [rubygem-openshift-origin-msg-broker-mcollective] release [1.30.1-1].
Automatic commit of package [openshift-origin-logshifter] release [1.8.1-1].