Move ssl detection to puma.rb [changelog skip]

[MSP-Greg]

Description

puma.rb loads puma/puma_http11, which contains the compiled c code for ssl. Move ssl detection from puma/detect.rb to puma.rb

Fix Puma::IS_WINDOWS and Puma.windows? to work with JRuby.

No breaking API changes.

JFYI, quick benchmark of predicate methods (Puma.ssl?) vs constants (Puma::HAS_SSL), showed constants were about twice as fast. But, both are 'fast enough'. Haven't looked thru the code to change...

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[nateberkopec]

Hmmm... why are we moving it? It looks like everything is still loaded in the same order, right? It feels cleaner to keep it in detect.

[MSP-Greg]

why are we moving it?

Since HAS_SSL is defined at loadtime, (and hence Puma.ssl?), puma/puma_http11 has to be loaded first. Currently I think it's loaded in puma.rb and one other file. I may have had an issue running a single test file, but also control_cli.rb uses methods from detect.rb. It doesn't load puma.rb, but it can if a 'start' command is issued.

So if detect.rb is loaded first, HAS_SSL is false, even though it may be true. By moving it to puma.rb, where the file that determines it is required, we avoid issues forever. That's why I added the comment that (I hope) states that only env/os related settings should be contained in detect.rb... I think that made sense...