Progress output

[jamesb93]

This adds progress output to command line processes with std::cout.

[weefuzzy]

Thanks for this @jamesb93!

Q: what do you need, ideally, for ReaCoMa in terms of output formatting? Thinking I might convert to a percentage for CLI users, as it's slightly more readable and will pave the way for a future progress bar thingy, but happy to add in some options so that you can have something easily parse-able from Lua if needed.

[jamesb93]

Ideally? Simple as possible is good so that it can be parsed out into a number. Second best case is there is a word near it like progress: 50% in which case the bits around the number should be the same length at all times.

Lua could quite flexibly work around whatever comes out as a long as its consistent. Thanks for consideirng me!

[weefuzzy]

Approved, pending some further experimentation by me about how to make it look nicer in terminal, and perhaps make the whole thing optional