Update typewriter.xml restoring type to text and updating the name of the effect

data/effects/typewriter.xml

 <!DOCTYPE kpartgui>
-<effect tag="typewriter" id="typewriter" type="hidden" unique="1">
-    <name>TypeWriter</name>
-    <description>Typewriter effect v0.3.3</description>
+<effect tag="typewriter" id="typewriter" type="text" unique="1">
+    <name>TypeWriter (for title clips)</name>
+    <description>Typewriter effect v0.3.3 To be applied on title clips only.</description>
     <author>Rafal Lalik</author>
     <parameter type="double" name="step_length" min="1" max="240" default="25">
         <name>Frames step</name>