Client enhancements to get crtime, file magic, and PE headers data

I used MSYS2 with MINGW to build libgnurx-0.dll and magic1.dll for Windows to be able to properly use python-magic.  The installer would also need to be modified to include the file magic database magic.mgc in the client installed directory.

I removed some packing detection and checksum comparison due to it having a pretty significant performance hit on larger binaries.  It may be worth it to enable those via options when a flow is run.

This also carves off the PKCS7 certs on PE files and returns them.  There might be better ways to do this.
I have mixed feelings about this.  The anomaly detection that I left in is the fast stuff.  The major slowdown happens when trying to actually compare the calculated checksum vs the checksum stored in the PE Header, particularly for large files.  I actually hesitate to even leave the checksum is zero check in because of how many times I have seen people assume that is a good indicator of evil, but it is "free" info and potentially useful so why not.  Checksum mismatches, particularly on "known" files is potentially very useful, but it usually winds up pretty low on the list of interesting features of a file.  

It might be better to separate the binary parsing stuff if it doesn't perform fast enough after some fixes and optimizations and then put the more expensive checks back in, but my initial feeling is that dropping the more expensive checks doesn't really result in a significant loss of information and gives a pretty large performance improvement when checking every file as part of normal stat operations.