ui: remove unused booleanfield

it's not used anymore, does not belong into pve-manager (rather in
proxmox-widget-toolkit), does not have a proper alias.

it's simple enough to recreate should we ever need it again

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

www/manager6/Makefile

@@ -19,7 +19,6 @@ JSSRC= 							\
 	form/AgentFeatureSelector.js			\
 	form/BackupModeSelector.js			\
 	form/BandwidthSelector.js			\
-	form/Boolean.js					\
 	form/BridgeSelector.js				\
 	form/BusTypeSelector.js				\
 	form/CPUModelSelector.js			\

www/manager6/form/Boolean.js

@@ -1,10 +0,0 @@
-// boolean type including 'Default' (delete property from file)
-Ext.define('PVE.form.Boolean', {
-    extend: 'Proxmox.form.KVComboBox',
-    alias: ['widget.booleanfield'],
-    comboItems: [
-	['__default__', gettext('Default')],
-	[1, gettext('Yes')],
-	[0, gettext('No')],
-    ],
-});