Add option for "TrimEnd" characters

[KerryRitter]

A lot of the C# POCOs I am converting end with "Dto" (some use ViewModel, etc). Adding a setting to enter in a string that will be trimmed off the end of any class name would be quite nice. I.e.

{
 "csharp2ts.trimEnd": "dto"
}

Which will convert ProjectVersionDto to ProjectVersion.

[RafaelSalguero]

I was already thinking on adding support for a configuration file in which I could add more options in the future. This seems great as the first option for that file.