Solve 500 errors being returned by server when creating users.

(rhbz746857)
Reinstate XmlRootElement on Account object.
Correct NullPointerException when accessing non-existing language memberships in the HAccount class.

common/zanata-common-api/src/main/java/org/zanata/rest/dto/Account.java

@@ -6,6 +6,7 @@
 
 import javax.xml.bind.annotation.XmlAttribute;
 import javax.xml.bind.annotation.XmlElement;
+import javax.xml.bind.annotation.XmlRootElement;
 import javax.xml.bind.annotation.XmlType;
 
 import org.codehaus.jackson.annotate.JsonIgnoreProperties;
@@ -19,6 +20,7 @@
 import org.zanata.rest.MediaTypes.Format;
 
 @XmlType(name = "accountType")
+@XmlRootElement(name = "account")
 @JsonIgnoreProperties(ignoreUnknown = true)
 @JsonPropertyOrder(
 {"email", "name", "username", "password"})

server/zanata-model/src/main/java/org/zanata/model/HPerson.java

@@ -118,7 +118,7 @@ public void setMaintainerProjects(Set<HProject> maintainerProjects)
    public Set<HLocale> getLanguageMemberships()
    {
       final Set<HLocale> memberships = new HashSet<HLocale>();
-      for( HLocaleMember locMem : this.languageTeamMemberships )
+      for( HLocaleMember locMem : this.getLanguageTeamMemberships() )
       {
          memberships.add( locMem.getSupportedLanguage() );
       }