Remove debugger gem

Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
Remove Gemfile.lock from .gitignore

Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
Commit Gemfile.lock

Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
Add letters generator

Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>