Remove dependency on System.Web.Routing

[Dashue]

Unfortunately this is a no go for me because of that dependency.

Running on NancyFx

[AlbertoMonteiro]

Could you suggetst a pull-request?

[philipbjorge]

@AlbertoMonteiro @mroach -- Is there still a dependency on System.Web.Routing?
It only seems like it matters for the MVC4Tests?

Specifically, I removed the reference on the RollbarSharp.csproj and everything built fine and tests passed. I'd expect something to go wrong if this was needed?

[richardversluis]

It is indirectly used in RequestModelBuilder, the RequestContext object.

https://github.com/mroach/RollbarSharp/blob/master/src/RollbarSharp/Builders/RequestModelBuilder.cs#L49