Changed auto registration behavior

The DisableAutoRegistration function on the ConfigurableBootstrapper
has been replaced by EnableAutoRegistration. This means that with this
patch, the auto-registration will be disabled by default instead of
enabled. The reason for this are primarily for performance but also
to help make tests be more implicit in setting up the context in
which they execute.
Renamed FakeNancyModule to ConfigurableNancyModule
Updated ConfigurableNancyModule

Added support for Patch and Options routes + renamed the nested
configurator class to align with the new name of the module class
Made member readonly
Bit of boyscouting and removed dead code
Moved type out of the Fakes namespace

The ConfigurableNancyModule is now located at the root of the
Nancy.Testing assembly.
Ignoring Nancy.Testing assembly

The AppDomainAssemblyTypeScanner will not scan Nancy.Testing when
it's been added to the default ignored assemblies. This prevents
it from finding stuff like the FakeNancyModule
Removed xunit dependency

The Nancy.Testing assembly used to have a dependency on Xunit, which
forces users to reference xunit no matter what framework they used
for their tests. The dependency was replace by our own Assert methods.
Removed xunit depenency from nuspec
Tying up some loose ends

- Added support for IComparable in the AssertEqualityComparer
- Added XML comments
- Moved classes to their own files
Merge pull request #652 from thecodejunkie/nancytestingremovexunitdependency-651

Removed the dependency on xunit in Nancy.Testing
Merge pull request #648 from thecodejunkie/nancytestingexcludefromautoregistration-647

Ignoring Nancy.Testing assembly
Merge pull request #646 from thecodejunkie/nancytestingfakemoduleupdate-645

Updated Nancy.Testing.Fakes.FakeNancyModule
Merge pull request #644 from thecodejunkie/nancytestingautoregistration-643

Changed auto registration behavior
Merge pull request #639 from thecodejunkie/writablerequestheaders-281

Made RequestHeaders writeable
Merge pull request #635 from thecodejunkie/istartupsplit-569

Split IStartup into IApplicationStartup and IApplicationRegistrations
Started adding more Dependency helpers
Updated Nancy.Testing to use CsQuery

Removed HtmlAgilityPack in favor of CsQuery. The same abstractions
are still used, they just wrap a different framework, giving us
the full power of the CsQuery CSS3 selectors.
Updated nuspec to include CsQuery dependency
Removed HtmlAgilityPack reference from nuspec