Change labels on submit form

[houndworks]

Now using User Submitted Posts plugin.

[houndworks]

No hooks for overriding code that assigns labels. But the labels are internationalised through po/mo files. Added custom houndstooth_en_GB language files, placed in houndstooth_extensions plugin. Also added hook to load this for USP pages.

[houndworks]

Looks like return to WPUF. USP doesn't manage multiple image uploads well.