Improve support for getting, setting, and comparing OCL element names

[dylanlerch]

Converter implementations sometimes need to manually write and compare names of OCL elements. The OclNamer on the OclConversionContext is not public, and this has resulted in us manually comparing and setting hard coded names in converters.

Potential changes to make improvements here

• Support the OclNameAttribute on more than just properties.
• Expose the OclNamer on the OclConversionContext
• Add some new methods to the OclNamer

Further investigation required

I will likely will need some more input on this one to make sure I'm not holding it wrong.