handle include

[BeckySharp]

now handling the include env in the same way as import

softened exceptions to printed warnings bc it was crashing (they weren't being caught) at runtime

[BeckySharp]

there aren't a ton of eqns to test this one, paper 1812.08535 has some (not in the little dev set you have, i can send if you want).
With this, the AABBs seem to be a little off, and they are not affected by either rescaling or attempts to increase the range of image resizings.
regardless of this, I think this is useful if for no other reason than equations, as include seems to be used to import files of custom macros

[marcovzla]

Can we take a look at the AABBs on monday?
Otherwise, LGTM.

[BeckySharp]

wouldn't it be funny if I responded with 👎 instead? I bet the thumbs up and down have VERY diff frequencies in github PR threads... :)

[marcovzla]

thanks!