Change build system over to CMake from Makefile.

More convenient for cross-platform development and allows me to use
XCode as an IDE without losing my Git history via use of generator.
Add encryption library for decrypting packets.
Include encryption library plus indendation/parenthesis fixes.
Remove "sylverant" include directive.

I happend to borrow the copy of these source files from the
Sylverant PSOBB server instead of Fuzziqer Software's, which
is why this is there.
Utilize command line arguments for server ip and device.

The idea is to make repetitive calls to this program easier
since it's likely that sessions will be restarted frequently.
Add TCPDump's sniffex.c source for the payload printing functions.

I may be guilty of laziness here, but in the interest of time I don't
want to rewrite these functions myself.
Move pcap timeout and replace struct fields with standard ints.

Using values from cstdint will make this program more portable.
Setting the read timeout on pcap prevents the OS from delaying
the delivery of packets to this program.
Add function for calculating the packet data offset in the callback.
Rewrite packet filter syntax.

The pcap_filter syntax is different than the tcpdump filter
syntax used previously. This was preventing packets from being
delivered correctly.