add filter for request param in utf8

+package org.legrog.configuration;
+
+import org.omnifaces.filter.CharacterEncodingFilter;
+
+import javax.servlet.annotation.WebFilter;
+
+/**
+ * ensure every request parameters (and so the content of forms in POST request) are done in utf-8
+ */
+@WebFilter("/*")
+public class Utf8CharacterEncodingFilter extends CharacterEncodingFilter {
+}