[IZPACK-1112] Merge Fix 

Merge fix for http://jira.codehaus.org/browse/IZPACK-1112 regarding PR #210

Changes from  IZPACK-1114 ( e7791acbc8ec50ba03704eeb26f8762feb122c7c ) have removed the following lines from AbstractPanels.java:
```
if (!(panel == null || executeValidationActions(panel, validate)))
    return false;
```
Since executeValidationActions was no longer being called saveData() method was also not being called. This causes the password field not to persist correctly when you reach a panel, add in some values, and hit previous.
I have just updated this branch with what is currently in master and applied a patch.