Fix repository mailing list editing which prevented field reset

releases.moxie

     text: ~
     security: ~
     fixes:
+    - Repository mailing lists could not be reset from the Edit Repository page (issue-399)
     - Ensure the Lucene ticket index is updated on repository deletion.
     changes:
     - Option to allow LDAP users to directly authenticate without performing LDAP searches

src/main/java/com/gitblit/wicket/pages/EditRepositoryPage.java

 
 					// set author metric exclusions
 					String ax = metricAuthorExclusions.getObject();
-					if (!StringUtils.isEmpty(ax)) {
+					if (StringUtils.isEmpty(ax)) {
+						repositoryModel.metricAuthorExclusions = new ArrayList<String>();
+					} else {
 						Set<String> list = new HashSet<String>();
 						for (String exclusion : StringUtils.getStringsFromValue(ax,  " ")) {
 							if (StringUtils.isEmpty(exclusion)) {
 
 					// set mailing lists
 					String ml = mailingLists.getObject();
-					if (!StringUtils.isEmpty(ml)) {
+					if (StringUtils.isEmpty(ml)) {
+						repositoryModel.mailingLists = new ArrayList<String>();
+					} else {
 						Set<String> list = new HashSet<String>();
 						for (String address : ml.split("(,|\\s)")) {
 							if (StringUtils.isEmpty(address)) {