Initial import of filter parser

Current runs as its own program, partially implemented.
Commiting for the sake of sharing access / backup.
Still needs a lot of work.
Move filter files into src/

- Makefile still needs work, is not compiling
Mildly working build process with argument parsing
Add support for holding an index instead of fieldname
Incredibly hacky evaluate implementation
Drop packets that don't pass the filter in recv
Build filter using CMake
adding ability to scan specific CIDR blocks or addresses.
Merge branch 'master' of github.com:zmap/zmap
Update build to -Werror, #pragma to ignore in lexer.l
compiling redis support
adding support for help text to output modules
adding null help text place holders
help to show selected output module name before printing help text
removing deprecated references to extended_file and simple_file.
making parse redis connstr externally available
Working filtering, still needs cleanup and optimization
Remove debug printf calls
Move stack.h and stack.c to lib
Untested iterative implementation of evaluate