Switch parser over to Prism

[kddnewton]

No description provided.

[MatthiasPortzel]

Some early results from running on careviso's monolith (I'm obviously excited). Unsurprising but still interesting.

Performance ⚡:
6.3.0:

real	0m5.149s

pair-down:

real	0m1.531s

Some differences don't bother me but I bothered to reduce a couple cases into failing tests.

%
def foo
# put one
puts 1
rescue => err
puts err
end
%
return(
bar(
# foo
foo
)
)
%
def foo
super { a = b if c }
end
%
# rubocop disable
def foo
puts 1
end
# rubocop enable
bar
%
format(
foooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
).strip
%
bar = [
"foooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo"
].abc.xyz
%
foo
# bar
%

[kddnewton]

Thanks @MatthiasPortzel! Yeah I'm still working through the various weird cases. I'll push to this branch once there is more progress.