Create shorter URS ids

[blakesweeney]

At PAG Tanya from TAIR suggested that we create shorter URS ids. She said that it is hard to write down an id when displayed in a talk. While we didn't want URS ids to be human readable we do show them to humans quite often. Thus we should make them human readable. So I agree with her, we should make them easier for people.

A simple way to this is to replace the string of 0's with a -. Our largest id is URS0000C8E9EF this would be written URS-C8E9EF. The smallest id is URS0000000001 which would be URS-1 in this system. I think this is a lot easier for people to read. We may want to add more separators (or at least allow them) if the hexadecimal number becomes too large. Initial work would be to allow this in url's and change the display on pages. We may want to accept these ids as input in our pipeline eventually as well.