Remove Vaadin prereleases and webjars repositories

Author: javier-godoy

pom.xml

@@ -62,16 +62,6 @@
             <id>Vaadin Directory</id>
             <url>https://maven.vaadin.com/vaadin-addons</url>
         </repository>
-        <repository>
-            <id>Vaadin prereleases</id>
-            <url>https://maven.vaadin.com/vaadin-prereleases</url>
-        </repository>
-        <!-- The bintray repository contain webjars immediately after generation. If the webjar is available
-             in Maven central, you do not need this repository -->
-        <repository>
-            <id>webjars</id>
-            <url>https://dl.bintray.com/webjars/maven</url>
-        </repository>
     </repositories>
 
     <dependencies>