Make Request keep original URI path

[jrochkind]

request.uri or something like that in rails.

Right now, we sometimes reconstruct the original URL from the data (eg in permalinks), but this can lead to a slightly different URL which sometimes works slightly differnetly. It's often preferable to be able to reconstruct the exact original URL sent to Umlaut, so we need to save it.

Then, make sure this carries on to permalinks somehow.

[jrochkind]

See #43

[jrochkind]

Closed for #43 combining issue