Add 'patent' to the set of contract words.

Change-Id: I3a4c2d10b5236a61e65292ce71c7a994c3f6213f

src/main/java/com/googlesource/gerrit/plugins/copyright/lib/CopyrightScanner.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/copyright/lib/CopyrightScanner.java b/src/main/java/com/googlesource/gerrit/plugins/copyright/lib/CopyrightScanner.java
index abcce95..2c056da 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/copyright/lib/CopyrightScanner.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/copyright/lib/CopyrightScanner.java
@@ -191,6 +191,7 @@
           "notwithstanding",
           "obligations?",
           "otherwise agreed",
+          "patents?",
           "perpetu(?:al|ity)",
           "phonorecords?",
           "prior written",