Improves support for specialversion

[dvdvliet]

I created this crude update to fix handling of version numbering containing multiple dashes.

This update supports:

• 1.0.0-rc-00260 (specialversion = "rc-00260")
• 2.0.0-umbraco-v8-20190325.23 (specialversion = "umbraco-v8-20190325.23")

This update does not support:

• 5.0.0.rc4.0

I also changed the argument order in the tests to match expected vs result.

[allisterb]

Hi thanks for this patch and sorry about the delay responding. Only minor issue I have is if AnyIdentifierChar and AnyIdentifier can be moved from the Core Grammar to the Nugetv2 grammar as I try to avoid changing the Core grammar unless absolutely needed. Other than that everything looks great. As soon as this is commited I'll update the NuGet package and the DevAudit build should pick up the changes.