patch utf8 encoding issues in @run
patch utf8 encoding issues in @type
respect language extensions when parsing code during @let

previously, @let would produce error messages, e.g.

<x> @let newtype Codensity f x = Codensity (forall r. (x -> f r) -> f r)
<lambdabot>  Parse failed: TypeOperators is not enabled
disable a couple of plugins
increase maximum message length
update @version output
patched libraries
log some system commands
modify @faq output
add current configuration and supporting scripts
update Pristine.hs