Add Support for VBA Component Files

[cyadehn]

Adds syntax for Visual Basic for Applications files exported from Office VBIDE

[alstr]

Thanks very much for the contribution.

I noticed a few issues when running the rests.

• Typo with assertEqual - I've fixed that.
• The tests are based on the ace_mode, not the language name, so I've removed the VBA tests and subsumed them under the Org ones with ace_mode: text.

That fixed the tests failing.

Current problems though:

• .sht files aren't recognised by languages.yml, and the test is only finding 2 of the 4 TODOs you added (hence why I updated the tests to look for 6 not 8).
• Given that these extensions are associated with multiple languages it is potentially going to be problematic linking the extension to a particular programming comment syntax unless it's the same for all of them. E.g. search for ".cls" in languages.yml and you get Apex, ObjectScript, VBA and others. I want to figure out a way around it, just not sure this very second.

[alstr]

Merged but with the caveats mentioned previously. Thanks.