Changes for better stand-alone ckanext-wet-boew usage

Hi @thriuin,

I've been using the ckanext-wet-boew as a base for another CKAN project, and have fixed a few design things that crop up when using ckanext-wet-boew standalone withough ckanext-canada on top of it.

Sorry this pull request is a bit bulky. There isn't actually that much going on, mostly quite minor changes. I should also note I haven't tested it yet with ckanext-canada on top, so do take a look before you might merge.

The changes are:
- Add WET dist repo as a submodule, so the user doesn't need to download and copy files. You can just do `git clone --recursive ...` and it will pull everything in.
- WET doesn't bundle jquery anymore, so included jquery as a static file.
- In the base template, better support for overriding styles and favicons.
- Everything else is just design tweaks