Update Marketplace install button

Author: adangel

README.md

@@ -10,7 +10,7 @@ Eclipse Update Site:
 *   Releases: <https://dl.bintray.com/pmd/pmd-eclipse-plugin/updates/>
 *   Snapshots: <https://dl.bintray.com/pmd/pmd-eclipse-plugin/snapshots/updates/>
 
-Marketplace: [![Drag to your running Eclipse* workspace. *Requires Eclipse Marketplace Client](https://marketplace.eclipse.org/sites/all/themes/solstice/public/images/marketplace/btn-install.png)](http://marketplace.eclipse.org/marketplace-client-intro?mpc_install=2755329 "Drag to your running Eclipse* workspace. *Requires Eclipse Marketplace Client")
+Marketplace: [![Drag to your running Eclipse workspace. Requires Eclipse Marketplace Client](https://marketplace.eclipse.org/sites/all/themes/solstice/public/images/marketplace/btn-install.png)](http://marketplace.eclipse.org/marketplace-client-intro?mpc_install=2755329)
 
 ## How to contribute