Operators for EDecimal

[WhiteBlackGoose]

Add <, > operators for EDecimal

[peteroupc]

I would do so, but I don't know whether and how I should do so, in the case of EDecimal; see these issues for more information:

• https://github.com/MicrosoftDocs/visualstudio-docs/issues/3728
• Advice on how to implement comparison operators for a type whose CompareTo is inconsistent with Equals dotnet/dotnet-api-docs#2937

[WhiteBlackGoose]

I'm not the one to help here, but I would make it consistent with CompareTo (like I'm doing it right now, because I'm writing a wrapper for your lib to compare numbers).