Add import order for java and javax. (#499)

* Add import order for java and javax.
* Remve the empty line between java and javax.
diff --git a/helix-style-intellij.xml b/helix-style-intellij.xml
index d14cec9..b3582a5 100644
--- a/helix-style-intellij.xml
+++ b/helix-style-intellij.xml
@@ -29,6 +29,9 @@
   <option name="NAMES_COUNT_TO_USE_IMPORT_ON_DEMAND" value="999" />
   <option name="IMPORT_LAYOUT_TABLE">
     <value>
+      <package name="java" withSubpackages="true" static="false" />
+      <package name="javax" withSubpackages="true" static="false" />
+      <emptyLine />
       <package name="" withSubpackages="true" static="false" />
       <emptyLine />
       <package name="" withSubpackages="true" static="true" />