Support for (mixed) MPLS and VLAN traffic, and a new default BPF

filter. (Seth Hall and Robin Sommer)

- Merging in the patch from #264, which provides support for mixed
  VLAN and MPLS traffic.

- Changing Bro's default filter from being built dynamically to being
  a static "ip or not ip". To get the old behaviour back (i.e., the
  dynamically built filter), redef "all_packets" to false.

- print-filter.bro now always prints the filter that Bro is actually
  using, even if overriden from the command line.

src/NetVar.h

@@ -264,6 +264,8 @@ extern int record_all_packets;
 extern RecordType* script_id;
 extern TableType* id_table;
 
+extern StringVal* cmd_line_bpf_filter;
+
 // Initializes globals that don't pertain to network/event analysis.
 extern void init_general_global_var();