Add new maintainers

manifest.xml

@@ -12,6 +12,8 @@
     <name>orogen-motion_planners</name>
     <maintainer>Sankar/[email protected]</maintainer>
     <maintainer>Rohit menon/[email protected]</maintainer>
+    <maintainer>Siddhant Kadwe/[email protected]</maintainer>
+    <maintainer>Vamsi Origanti/[email protected]</maintainer>
     <stage>-1</stage>
     <keywords>
         <keyword>planning</keyword>