adding i18n title capability for generic lists

Currently, Generic Lists only allow for a single title. This pull request adds fields to the dialog for localized titles. It is heavily based on the Tag i18n capability. So much so that it seems to me that we don't need a separate configuration location for the locale list to drive the dialog - it should be reused from /etc/tags@languages.

Here's what the dialog looks like once the languages are loaded:
![test1](https://cloud.githubusercontent.com/assets/65906/3883196/ebd4f76a-219e-11e4-9519-b71bf83eaee9.png)

Strictly speaking `Resource.adaptTo(ValueMap.class)` can always return null. The new method `Resource.getValueMap()` will not, but that was only added in AEM 6. Since I was in this class anyway, I made the switch.