Impove string-contained code snippets

[Dennis-Petrov]

cresn/cesn code snippets should generate string type name:

    Contract.Ensures(!string.IsNullOrEmpty(Contract.Result<string>()));
    Contract.Requires<ArgumentException>(!string.IsNullOrEmpty(arg));

instead of String:

    Contract.Ensures(!String.IsNullOrEmpty(Contract.Result<string>()));
    Contract.Requires<ArgumentException>(!String.IsNullOrEmpty(arg));

Also, something like cresnw/cesnw will be suitable:

    Contract.Ensures(!string.IsNullOrWhitespace(Contract.Result<string>()));
    Contract.Requires<ArgumentException>(!string.IsNullOrWhitespace(arg));

I know, that I could fix/add snippets by myself, but out-of-the-box always better :).

[sharwell]

I completely agree!

Want to try your hand at a pull request? The snippets are located here.

[Dennis-Petrov]

Sure, I didn't know that I can add something here. :)

[Dennis-Petrov]

New snippets are included in RC.