UseJava: add INCLUDE_MODULES argument to add_jar

Arguments are added to the dependencies list, and to the "--module-path"
passed to javac, which is only generated for adequate JDK versions.

Tests/JavaModExportImport/Import/CMakeLists.txt

@@ -0,0 +1,14 @@
+project(import Java)
+
+cmake_minimum_required(VERSION 3.10)
+set(CMAKE_VERBOSE_MAKEFILE 1)
+
+find_package(Java COMPONENTS Development)
+include(UseJava)
+
+find_package(JavaBuildExportTest REQUIRED)
+find_package(JavaInstallExportTest REQUIRED)
+
+add_jar(${PROJECT_NAME}
+  SOURCES Import.java module-info.java
+  INCLUDE_MODULES foo::foo bar::bar)

Tests/JavaModExportImport/Import/Import.java

@@ -0,0 +1,13 @@
+import org.foo.Foo;
+import com.bar.Bar;
+
+class Import
+{
+  public static void main(String args[])
+  {
+    Foo foo = new Foo();
+    Bar bar = new Bar();
+    foo.printName();
+    bar.printName();
+  }
+}

Tests/JavaModExportImport/Import/module-info.java

@@ -0,0 +1,4 @@
+module client {
+    requires mod_foo;
+    requires mod_bar;
+}