pcap library capture support

In some cases SOCK_RAW does not capture vlan tag, and
generates a stripped packet. This happens on recent linux
which has PACKET_AUXDATA in <linux/if_packet.h>.
Compiling with -DWITH_PCAP -lpcap will create a libpcap
enabled version of trema switch.
pcap library capture support

In some cases SOCK_RAW does not capture vlan tag, and
generates a stripped packet. This happens on recent linux
which has PACKET_AUXDATA in <linux/if_packet.h>.
Compiling with -DWITH_PCAP -lpcap will create a libpcap
enabled version of trema switch.
Merge branches 'with_pcap' and 'with_pcap' of https://github.com/iHiroakiKawai/trema-edge into with_pcap
pcap library capture support

In some cases SOCK_RAW does not capture vlan tag, and
generates a stripped packet. This happens on recent linux
which has PACKET_AUXDATA in <linux/if_packet.h>.
Compiling with -DWITH_PCAP -lpcap will create a libpcap
enabled version of trema switch.
Merge branches 'with_pcap' and 'with_pcap' of https://github.com/iHiroakiKawai/trema-edge into with_pcap
pcap library capture support

In some cases SOCK_RAW does not capture vlan tag, and
generates a stripped packet. This happens on recent linux
which has PACKET_AUXDATA in <linux/if_packet.h>.
Compiling with -DWITH_PCAP -lpcap will create a libpcap
enabled version of trema switch.
Merge branches 'with_pcap' and 'with_pcap' of https://github.com/iHiroakiKawai/trema-edge into with_pcap
drop the packet if pcap_sendpacket fails

because there're nothing what we can do for it.
We go forward and remove that packet from the queue.
Merge branch 'with_pcap' of https://github.com/iHiroakiKawai/trema-edge into iHiroakiKawai-with_pcap
Beautify.