R1:237ca095a6b9

Trim trailing whitespace from user realnames

Summary: Fixes T3069. Ref T3516. For a long time, LDAP import added trailing whitespace to real names when importing them (for example, `"John Smith"` would be imported as `"John Smith "`). We no longer do this, but should clean up the database since it seems highly unlikely that any user wants trailing whitespace in their real name.

Test Plan:
$ ./bin/storage upgrade -f --apply phabricator:20130711.trimrealnames.php
Applying patch 'phabricator:20130711.