Add linter to check for binaries accidentally added to repository

This should catch mistakes like
a703fbce20969e6f02e74fee76c0a9e22b513426.

Adds an arcanist-external-json-linter submodule, which should eventually
be mirrored on haskell.org resources.

Test Plan: Validate

Reviewers: thomie, hvr, austin

Reviewed By: austin

Differential Revision: https://phabricator.haskell.org/D1515

1 files changed, 4 insertions, 0 deletions

diff --git a/.arclint b/.arclint
index 8f83776f80..1b135075d0 100644
--- a/.arclint
+++ b/.arclint
@@ -52,6 +52,10 @@
       "severity": {
         "2": "disabled"
       }
+    },
+    "check-binaries": {
+      "type": "external-json",
+      "external-json.script": "python .arc-linters/check-binaries.py"
     }
   },