[FAB-9285] Escape periods in filenames for license chk

Properly escape periods in filename wildcard patterns when
excluding filenames for license checking. And while we're here,
might as well prettify the exclusion list so it's easier to read.

Change-Id: Ia596ebdfd2c250b8f6644f49a10e06d7f786802f
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>

scripts/check_license.sh

@@ -6,10 +6,24 @@
 #
 
 function filterExcludedFiles {
-  CHECK=`echo "$CHECK" | grep -v .png$ | grep -v .rst$ | grep -v ^.git/ \
-  | grep -v .pem$ | grep -v .block$ | grep -v .tx$ | grep -v ^LICENSE$ | grep -v _sk$ \
-  | grep -v .key$ | grep -v \\.gen.go$ | grep -v ^Gopkg.lock$ | grep -v 'testdata/' \
-  | grep -v .md$ | grep -v ^vendor/ | grep -v ^.build/ | grep -v .pb.go$ | sort -u`
+  CHECK=`echo "$CHECK" \
+		| grep -v "^\.git/" \
+		| grep -v "^\.build/" \
+		| grep -v "^vendor/" \
+		| grep -v "testdata/" \
+		| grep -v "^LICENSE$" \
+		| grep -v "\.png$" \
+		| grep -v "\.rst$" \
+		| grep -v "\.pem$" \
+		| grep -v "\.block$" \
+		| grep -v "\.tx$" \
+		| grep -v "_sk$" \
+		| grep -v "\.key$" \
+		| grep -v "\.gen\.go$" \
+		| grep -v "^Gopkg\.lock$" \
+		| grep -v "\.md$" \
+		| grep -v "\.pb\.go$" \
+		| sort -u`
 }
 
 CHECK=$(git diff --name-only --diff-filter=ACMRTUXB HEAD)