Added module keywords to Java. (#1655)

This adds the in Java 9 introduced module keywords to Java.
Namespaces following these keywords are also properly highlighted.

components/prism-java.js

@@ -1,6 +1,6 @@
 (function (Prism) {
 
-	var keywords = /\b(?:abstract|continue|for|new|switch|assert|default|goto|package|synchronized|boolean|do|if|private|this|break|double|implements|protected|throw|byte|else|import|public|throws|case|enum|instanceof|return|transient|catch|extends|int|short|try|char|final|interface|static|void|class|finally|long|strictfp|volatile|const|float|native|super|while|var|null)\b/;
+	var keywords = /\b(?:abstract|continue|for|new|switch|assert|default|goto|package|synchronized|boolean|do|if|private|this|break|double|implements|protected|throw|byte|else|import|public|throws|case|enum|instanceof|return|transient|catch|extends|int|short|try|char|final|interface|static|void|class|finally|long|strictfp|volatile|const|float|native|super|while|var|null|exports|module|open|opens|provides|requires|to|transitive|uses|with)\b/;
 
 	// based on the java naming conventions
 	var className = /\b[A-Z](?:\w*[a-z]\w*)?\b/;
@@ -35,7 +35,7 @@
 			lookbehind: true
 		},
 		'namespace': {
-			pattern: /\b(package\s+|import\s+(?:static\s+)?)[a-z]\w*(\.[a-z]\w*)+/,
+			pattern: /(\b(?:exports|import(?:\s+static)?|module|open|opens|package|provides|requires|to|transitive|uses|with)\s+)[a-z]\w*(\.[a-z]\w*)+/,
 			lookbehind: true,
 			inside: {
 				'punctuation': /\./,

tests/languages/java/keyword_feature.test

@@ -20,6 +20,9 @@ finally long
 strictfp volatile const
 float native super while
 var null
+module requires transitive
+exports uses open
+opens with to provides
 
 ----------------------------------------------------
 
@@ -45,7 +48,10 @@ var null
 	["keyword", "finally"], ["keyword", "long"],
 	["keyword", "strictfp"], ["keyword", "volatile"], ["keyword", "const"],
 	["keyword", "float"], ["keyword", "native"], ["keyword", "super"], ["keyword", "while"],
-	["keyword", "var"], ["keyword", "null"]
+	["keyword", "var"], ["keyword", "null"],
+	["keyword", "module"], ["keyword", "requires"], ["keyword", "transitive"],
+	["keyword", "exports"], ["keyword", "uses"], ["keyword", "open"],
+	["keyword", "opens"], ["keyword", "with"], ["keyword", "to"], ["keyword","provides"]
 ]
 
 ----------------------------------------------------

tests/languages/java/module_feature.test

@@ -0,0 +1,158 @@
+module com.js.prism {
+    exports java.net.http;
+    exports jdk.internal.editor.spi to jdk.jshell;
+
+    requires java.base;
+    requires transitive java.xml;
+
+    uses java.net.ContentHandlerFactory;
+
+    opens java.time.DateTime;
+    opens java.time.LocalDateTime to java.logging;
+
+    provides com.modules.hello.HelloInterface with com.modules.hello.HelloModules;
+
+}
+
+
+----------------------------------------------------
+  [
+  ["keyword", "module"],
+  ["namespace",
+    ["com",
+      ["punctuation", "."],
+      "js",
+      ["punctuation", "."],
+      "prism"
+    ]
+  ],
+  ["punctuation",  "{"],
+
+  ["keyword", "exports"],
+  ["namespace", 
+    [
+      "java",
+      ["punctuation", "."],
+      "net",
+      ["punctuation", "."],
+      "http"
+    ]
+  ],
+  ["punctuation", ";"],
+
+  ["keyword",   "exports"],
+  ["namespace", 
+    [
+      "jdk",
+      ["punctuation", "."],
+      "internal",
+      ["punctuation", "."],
+      "editor",
+      ["punctuation", "."],
+      "spi"
+    ]
+  ],
+  ["keyword",   "to"],
+  ["namespace", 
+    [
+      "jdk",
+      ["punctuation", "."],
+      "jshell"
+    ]
+  ],
+  ["punctuation", ";"],
+
+  ["keyword",   "requires"],
+  ["namespace", 
+    [
+      "java",
+      ["punctuation", "."],
+      "base"
+    ]
+  ],
+  ["punctuation", ";"],
+
+  ["keyword",   "requires"],
+  ["keyword",   "transitive"],
+  ["namespace", 
+    [
+      "java",
+      ["punctuation", "."],
+      "xml"
+    ]
+  ],
+  ["punctuation", ";"],
+
+  ["keyword",   "uses"],
+  ["namespace", 
+    [
+      "java",
+      ["punctuation", "."],
+      "net"
+    ]
+  ],
+  ["punctuation", "."],
+  ["class-name",   "ContentHandlerFactory"],
+  ["punctuation", ";"],
+
+  ["keyword",   "opens"],
+  ["namespace", 
+    [
+      "java",
+      ["punctuation", "."],
+      "time"
+    ]
+  ],
+  ["punctuation", "."],
+  ["class-name",   "DateTime"],
+  ["punctuation", ";"],
+  ["keyword",   "opens"],
+  ["namespace", 
+    [
+      "java",
+      ["punctuation", "."],
+      "time"
+    ]
+  ],
+  ["punctuation", "."],
+  ["class-name",   "LocalDateTime"],
+  ["keyword",   "to"],
+  ["namespace", 
+    [
+      "java",
+      ["punctuation", "."],
+      "logging"
+    ]
+  ],
+  ["punctuation", ";"],
+  ["keyword",   "provides"],
+  ["namespace", 
+    [
+      "com",
+      ["punctuation", "."],
+      "modules",
+      ["punctuation", "."],
+      "hello"
+    ]
+  ],
+  ["punctuation", "."],
+  ["class-name",   "HelloInterface"],
+  ["keyword",   "with"],
+  ["namespace", 
+    [
+      "com",
+      ["punctuation", "."],
+      "modules",
+      ["punctuation", "."],
+      "hello"
+    ]
+  ],
+  ["punctuation", "."],
+  ["class-name",   "HelloModules"],
+  ["punctuation", ";"],
+  ["punctuation", "}"]
+]
+
+----------------------------------------------------
+
+Checks for module definition.