Add hard dependency to Java module in plugin.xml

Otherwise resulting plugin will be installable to PyCharm, WebStorm and
other Intellij IDE without Java.

It can be resolved with `xi:include`, but it should be done with care,
because some declarations in `jvm.xml` should be placed after some
declarations in `plugin.xml` (action groups suffer from this issue for
sure).

idea/src/META-INF/plugin.xml

@@ -28,6 +28,7 @@
   <!-- ULTIMATE-PLUGIN-PLACEHOLDER -->
 
   <!-- CLION-PLUGIN-PLACEHOLDER-START -->
+  <depends>com.intellij.modules.java</depends>
   <depends optional="true" config-file="jvm.xml">com.intellij.modules.java</depends>
   <depends optional="true" config-file="javaScriptDebug.xml">JavaScriptDebugger</depends>
   <!-- CLION-PLUGIN-PLACEHOLDER-END -->