Initial commit
Added Makefile

Using Michael Crawford's generic makefile:
https://github.com/mbcrawfo/GenericMakefile

Make seems to default to g++ for CXX for me, so I switched ?= to =.
Updated Makefile

-stdlib=libc++ is necessary for both compilation and linking
-lc++abi is necessary for linking
disabled a few unnecessary warnings
Implemented file handling

Added control flow for processing command line args or recieving data
from stdin.
Added namespace wf.
Added wf::ScanFiles, which loops through files, but does not yet do any
processing other than trying to open each file.
Cleaned up namespace usage in ScanFiles
Added helper function StripPunct
Fixed whitespace errors
Included necessary headers for StripPunct
Added helper function StrToLower
Added std::exception handler
Switched debug flag to debug mode only

Debug builds from clang seem to take a noticeable performance hit.
I think it would be best to test with release builds and only build with
the debug flag when it is actually needed for debugging.
Cleaned up formatting in StripPunct
Updated include documentation for tolower
Implemented UpdateFreq function

This is the last major implementation-level detail. All that is left is
providing a nice interface to it, refactoring, and adding new features
in the future!
Switched from libc++ to libstdc++

I notice a considerable speedup (8x) when compiling with libstdc++. No
idea why this is the case, but I feel that it justifies this switch.
Cleaned up formatting in anonymous namespace

There is now more liberal usage of type deduction and using namespace
std within the anonymous namespace.
Updated include docs