Fix lint.sh on macOS (sergi#62)

Author: maksimov

scripts/lint.sh

@@ -5,18 +5,18 @@ if [ -z ${ROOT_DIR+x} ]; then echo "ROOT_DIR is not set"; exit 1; fi
 
 echo "gofmt:"
 OUT=$(gofmt -l $ROOT_DIR)
-if [ $(echo -n "$OUT" | wc -l) -ne 0 ]; then echo "$OUT"; PROBLEM=1; fi
+if [ $(echo "$OUT\c" | wc -l) -ne 0 ]; then echo "$OUT"; PROBLEM=1; fi
 
 echo "errcheck:"
 OUT=$(errcheck $PKG/...)
-if [ $(echo -n "$OUT" | wc -l) -ne 0 ]; then echo "$OUT"; PROBLEM=1; fi
+if [ $(echo "$OUT\c" | wc -l) -ne 0 ]; then echo "$OUT"; PROBLEM=1; fi
 
 echo "go vet:"
 OUT=$(go tool vet -all=true -v=true $ROOT_DIR 2>&1 | grep --invert-match -P "(Checking file|\%p of wrong type|can't check non-constant format)")
-if [ $(echo -n "$OUT" | wc -l) -ne 0 ]; then echo "$OUT"; PROBLEM=1; fi
+if [ $(echo "$OUT\c" | wc -l) -ne 0 ]; then echo "$OUT"; PROBLEM=1; fi
 
 echo "golint:"
 OUT=$(golint $PKG/... | grep --invert-match -P "(method DiffPrettyHtml should be DiffPrettyHTML)")
-if [ $(echo -n "$OUT" | wc -l) -ne 0 ]; then echo "$OUT"; PROBLEM=1; fi
+if [ $(echo "$OUT\c" | wc -l) -ne 0 ]; then echo "$OUT"; PROBLEM=1; fi
 
 if [ -n "$PROBLEM" ]; then exit 1; fi