Show only folders for selecting converter binaries

cps/templates/config_edit.html

@@ -327,7 +327,7 @@
            <div class="form-group input-group">
            <input type="text" class="form-control" id="config_binariesdir" name="config_binariesdir" value="{% if config.config_binariesdir != None %}{{ config.config_binariesdir }}{% endif %}" autocomplete="off">
            <span class="input-group-btn">
-             <button type="button" data-toggle="modal" id="binaries_modal_path" data-link="config_binariesdir" data-target="#fileModal" class="btn btn-default"><span class="glyphicon glyphicon-folder-open"></span></button>
+             <button type="button" data-toggle="modal" id="binaries_modal_path" data-link="config_binariesdir" data-folderonly="true" data-target="#fileModal" class="btn btn-default"><span class="glyphicon glyphicon-folder-open"></span></button>
            </span>
            </div>
            <div class="form-group">