TIKA-1735 - add AC1027 and AC1032 and add ability to use dwgread if it is installed.

[nddipiazza]

Add parsing support for AC1027 and AC1032. If dwgread is installed, use it to parse the document.

Test data is from https://github.com/LibreDWG/libredwg/tree/master/test/test-data/2018

[tballison]

I realize this will require quite a bit more refactoring. Would it make sense to create a new parser DWGExecParser that runs dwgread if it is installed, otherwise falls back to the current parser as it is? I worry that the new parser is a bit complex.

[nddipiazza]

oops didn't see this coment until now. @tballison yes that is fine. I'll see if i can get this done this weekend.

[monkmachine]

@nddipiazza just wondering if you got anywhere with this?

[nddipiazza]

@monkmachine hi i did not end up needing this for my project and abandoned ship. you need it? it needs a couple hours of effort applying the fixes tim suggested.

[monkmachine]

@nddipiazza Yeah would be good, we're about to start doing some work with DWG's.

[monkmachine]

@tballison this can be closed now as you've just merged my PR :)

[tballison]

Closing because of merge of #558