network: complete field ppp, add virtual key and update nm_autogen to
support front-end widget properties
network: update nm_autogen, GetAllKeysInField()
network: update autogen code, sort key order
network: add virtual key to toggle connection permission
network: add code for field vpn
network: update nm_autogen, support virtual field
network: support vpn-l2tp connection type
network: complete support for vpn l2tp
network: add generalGetConnectionType(), support multi vpn types
network: add support for vpn openconnect