Add test cscope.out and tags file (related to #16)

This pull request is related to #16 and adds a `./test/cscope.out` and `./test/tags` files.
The goal is to enable installation test for `brew` package manager.

In order to keep `cscope.out` file small, it is generated only for this file: `./build/CMakeFiles/3.0.1/CompilerIdC/CMakeCCompilerId.c`.

If we generated `cscope.out` for the whole project it would be ~ 4.5Mb large!

With files in the project, after installation we can easily perform independent,
automated test, example:

    # test generating the DB
    $ cqmakedb -s ./test/codequery.db -c ./test/cscope.out -t ./test/tags -p
    # test DB search
    $ cqsearch -s ./test/codequery.db -t 'info_platform'