freqdbbuilder: Rename the built executable

This way, it is in the same namespace as all the others
we install.
util: Comment on our utilities

If we ever grow our number of little helper functions, it
might be good idea at some point to start looking into reusing
alternatives from other libraries.

The 2 ones we have currently exist in Boost, so let's keep
track of it, in case we ever decide to switch to it in the
future.
cli: CNY cleanup

This drops all the useless commented code, as well as the unneeded
#include's
dbbuilder: CNY cleanup

This drops some leftover debug code, remove old useless comments, extra
empty lines, etc...
dbbuilder: This is an error

Errors should be written to stderr, not stdout.

This is especially problematic because when running the dbbuilder
at build time, we redirect stdout to /dev/null, and as such would
miss this message.
dbbuilder: Add some comments

The code is about to get slightly more complex, so these
will help.
Merge pull request #17 from bochecha/master

Cleanup, and big refactoring of the frequency code