BZ1047469 - PHP cart: fixes pear package upgrade and downgrade messages

It checks the versions of currently installed and
desired packages. It prints a helpful message
about clean build if the user would like to downgrade
a package.
Bug 1123587 - Added OPENSHIFT_POSTGRESQL_DATESTYLE env var
Merge pull request #5682 from mfojtik/datestyle

Merged by openshift-bot
BZ1047469 - PHP cart pear downgrade enhancement: exit when it's failed
Merge pull request #5681 from vbalazs/bvarga/bz_1047469_pear_package_upgrade_fail_message

Merged by openshift-bot
Update mongo env var documentation
Merge pull request #5684 from kevinconaway/master

Merged by openshift-bot