Add some simple test cases for the protobuf language

This patch adds basic test cases for the protobuf language and
fixes some whitespace issues. It also adds the missing
requirement to the clike language to components.js.

components.js

@@ -399,6 +399,7 @@ var components = {
 		},
 		"protobuf": {
 			"title": "Protocol Buffers",
+			"require": "clike",
 			"owner": "just-boris"
 		},
 		"puppet": {

components/prism-protobuf.js

@@ -1,8 +1,8 @@
 Prism.languages.protobuf = Prism.languages.extend('clike', {
-    keyword: /\b(package|import|message|enum)\b/,
-    builtin: /\b(required|repeated|optional|reserved)\b/,
-    primitive: {
-        pattern: /\b(double|float|int32|int64|uint32|uint64|sint32|sint64|fixed32|fixed64|sfixed32|sfixed64|bool|string|bytes)\b/,
-        alias: 'symbol'
-    }
+	keyword: /\b(package|import|message|enum)\b/,
+	builtin: /\b(required|repeated|optional|reserved)\b/,
+	primitive: {
+		pattern: /\b(double|float|int32|int64|uint32|uint64|sint32|sint64|fixed32|fixed64|sfixed32|sfixed64|bool|string|bytes)\b/,
+		alias: 'symbol'
+	}
 });

tests/languages/protobuf/keyword_feature.test

@@ -0,0 +1,40 @@
+message Point {
+  required int32 x = 1;
+  required int32 y = 2;
+  optional string label = 3;
+}
+
+----------------------------------------------------
+
+[
+	["keyword", "message"],
+	" Point ",
+	["punctuation", "{"],
+
+	["builtin", "required"],
+	["primitive", "int32"],
+	" x ",
+	["operator", "="],
+	["number", "1"],
+	["punctuation", ";"],
+
+	["builtin", "required"],
+	["primitive", "int32"],
+	" y ",
+	["operator", "="],
+	["number", "2"],
+	["punctuation", ";"],
+
+	["builtin", "optional"],
+	["primitive", "string"],
+	" label ",
+	["operator", "="],
+	["number", "3"],
+	["punctuation", ";"],
+
+	["punctuation", "}"]
+]
+
+----------------------------------------------------
+
+Check for keywords and builtins

tests/languages/protobuf/string_feature.test

@@ -0,0 +1,23 @@
+""
+''
+"foo"
+'foo'
+"'foo'"
+'"bar"'
+"  // comment  "
+
+----------------------------------------------------
+
+[
+	["string", "\"\""],
+	["string", "''"],
+	["string", "\"foo\""],
+	["string", "'foo'"],
+	["string", "\"'foo'\""],
+	["string", "'\"bar\"'"],
+	["string", "\"  // comment  \""]
+]
+
+----------------------------------------------------
+
+Checks for single-quoted and double-quoted strings.