Allow switching of -no-shell-escape flag

[bomb-on]

Passing allow_shell_escape=True to build_pdf() would switch the default -no-shell-escape flag into -shell-escape.

[mbr]

If this is still current, I do not think this is the right way to go about it -- I think it'd be better to derive a custom builder, like InsecurePDFLatexBuilder (if you wish, you can substitute "Trusted" for "Insecure" ;)).

The reason for this is that not every conceivable Builder necessarily has shell escapes. Correct me if I'm wrong there!

[tom-f-oconnell]

This issue is still relevant. I personally don't think there's much more than aesthetic difference between the solution you're describing and the one in the pull request, and I like the minimal extra code in the pull request's solution.

It doesn't seem like such a problem that builders not using this flag would just silently ignore the keyword argument. Additionally, such builders are also only hypothetical right now, as all of the builders currently implemented do have these shell escape flags. People who implement additional builders could err if there are unrecognized keyword arguments, if they so choose.

Since we already have this fix, absent someone willing to implement it as you envision, I would appreciate this being merged. Until then, I'll just depend on a fork with this patch in the mean time.