Add `grunt phpunit` which runs three tasks: phpunit, ajax tests, and phpunit as multisite.

You can also run `grunt phpunit:default`, `grunt phpunit:ajax`, and grunt `phpunit:multisite` separately.

`grunt test` now runs the qunit task (both compiled and uncompiled scripts) and the phpunit tasks.

props bpetty.
fixes #25854, see #25781.


git-svn-id: https://develop.svn.wordpress.org/trunk@26064 602fd350-edb4-49c9-b593-d223f7449a82
Avoid JSHint errors. Use dot notation when able and declare pwsL10n as a global.

props jorbin.
fixes #25870.


git-svn-id: https://develop.svn.wordpress.org/trunk@26065 602fd350-edb4-49c9-b593-d223f7449a82