Convert plain Makefile into cmake

As promised via mail I finally got around to convert the buildsystem into cmake. Please contact me for suggestion or enhancements.

The package can be configured with 4 different options:

-DWITH_REDIS=ON

Enable support for Redis DB

-DWITH_JSON=ON

Enable support for JSON based output

-DENABLE_DEVELOPMENT=ON

Enable all warnings and make them fatal

-DENABLE_HARDENING=ON

Compile and link with some hardening

Use the new system by creating a build directory and change into that.
And then call the following

cmake -DWITH_REDIS=OFF -DWITH_JSON=ON \
-DENABLE_DEVELOPMENT=ON -DENABLE_HARDENING=ON /path/to/source/dir/
make
make DESTDIR="/..." install

Signed-off-by: Justin Lecher <jlec@gentoo.org>