Servers from config

@danfruehauf took over.

This PR now includes:
 * Servers in config file (work by @dnahodil)
 * Controller function `server/getInfo` - returns server information from config file
   * Tests
 * JS code to use `server/getInfo` and act on the server type
   * Remove the ugly hack of looking for ncwms layers by having `/ncwms/wms` in the URL

This can now be reviewd.

# Original message by @dnahodil:

*Ready for someone to take over - feel free to contact me for any questions*

This is a start on the work to have Servers configured in config files rather than in the database. I have added Server config to config.groovy in a way that I think will work but feedback on this approach is welcomed. I have updated HostVerifier so that proxy requests use the new Server configuration to validate proxy URLs. There are other usages of Servers which haven't been changed over, yet.