mysql cart: user-settable start timeout

Increase startup timeout for MySQL cart to 45 seconds, allow setting
`start` timeout via `OPENSHIFT_MYSQL_START_TIMEOUT` user env var and
`stop` timeout via `OPENSHIFT_MYSQL_STOP_TIMEOUT`.

Enterprise bug 1106450
https://bugzilla.redhat.com/show_bug.cgi?id=1106450
Bug 1135617 - AVC denied messages when creating new gears
Merge pull request #5785 from dobbymoodge/mysql_cart_BZ1106450

Merged by openshift-bot
Merge pull request #5786 from brenton/BZ1135617

Merged by openshift-bot
Automatic commit of package [rubygem-openshift-origin-node] release [1.30.3-1].
Automatic commit of package [openshift-origin-cartridge-jbosseap] release [2.20.2-1].
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Automatic commit of package [rubygem-openshift-origin-console] release [1.30.2-1].
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Automatic commit of package [openshift-origin-broker-util] release [1.29.2-1].
Automatic commit of package [openshift-origin-node-util] release [1.29.2-1].
bump spec for tag fix
Automatic commit of package [rubygem-openshift-origin-msg-broker-mcollective] release [1.29.1-1].