Add oppressive language presubmit

BUG=b:162024466
TEST=try to upload a CL with a blocked term

Change-Id: Ib7ffaa2a6a302bf74c0d6aaf67bab0f61c3da5bc
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/optofidelity_chrome_touch_client/+/2683220
Tested-by: Sean O'Brien <seobrien@chromium.org>
Auto-Submit: Sean O'Brien <seobrien@chromium.org>
Reviewed-by: Harry Cutts <hcutts@chromium.org>
Commit-Queue: Harry Cutts <hcutts@chromium.org>
diff --git a/unblocked_terms.txt b/unblocked_terms.txt
new file mode 100644
index 0000000..60264eb
--- /dev/null
+++ b/unblocked_terms.txt
@@ -0,0 +1,6 @@
+# KEEP THIS COMMENT IN YOUR COPY.
+#
+# Don't delete this file if you want to keep keyword_check enabled even if it's
+# empty.
+#
+# See repohooks/README.md for more details.