Add filter plugins by name

#### Added a LineEdit field to the plugin dialog for filtering the plugins by using the plugin name.
* filtering is case-**in**sensitive
* when changing the "type" with the combobox (all, installed...) then the filter field is cleared so all plugin is visible again from the selected group "type"
    * because if it is not cleared then maybe the user forget the filter field and then he think that the selected group is empty