When doing a git grep (of rustc-dev-guide or of rust-lang/rust with
--recurse-submodules), if the grep happens to match within the minified
javascript, the resulting long single lines can cause a text pager or
editor to slow down and distract from more useful matches.
Minified javascript isn't formatted for human consumption, by
definition, so mark it as binary, which causes git grep to instead just
state that it matches without printing the matching "line".
Josh Triplett
jethrogb
Vadim Petrochenkov