FE/VBoxManage: std::string::find returns npos not -1 if nothing matches

Frontends/VBoxManage: squash compiler warning

NetworkServices: coding style

Frontends: Whitespace and svn:keywords cleanups by scm.

NAT/Loopback mapping: changes semantically unrelated symbol ";" with more expressive "=" for map opperation. VBoxManage natnework modify -t nat-test-1 -l "127.0.1.3=8"

Port-forwarding/win: INET6_ADDRSTRLEN is defined in ws2ipdef.h and has value 65, opositely to BSD where it defined as 47. XXX: including in VBoxManageNATNetwork.cpp winsock*.h and ws2* produce hard to fix mess of definitions, that why value locally defined as 65.

VBoxManage natnetwork help

VBoxManage: coding style

VBoxManage/NATNetwork: adds -l(--loopback-4) and -L(--loopback-6) usage VBoxManage natnetwork modify -t nat-test-1 -l "127.0.1.3;8" adds mapping 127.0.1.3 to network id (of nat-test-1) +8 -L adds offset for IPv6 case.

VBoxManage/natnetwork: include list on windows.

include VBox/com/EventQueue only if necessary

NAT/LWIP service: nits. (cosmetic).

NAT/Lwip-service: Main client now, dynamic port-forward + managment.

tabs

Frontends/VBoxManage: listing/manipulating nat networks if VBOX_WITH_NAT_SERVICE is defined.