Request

First of all, thanks for doing the way I imagined the hardmode should be (:

I did some refactoring in variables, just organizing the code.
The way a changed the messages solves the request [23](https://github.com/takac/vim-hardtime/pull/23).

I think that if you want some plugin, it must be loaded automatically and that's the way most of the plugins work. Also, the messages tell the hardmode is enabled by default.

I added insert keys because sometimes I end up pressing the arrows keys for the habit of others applications - its a shame not every application is vim-like ):
And its nice for who is learning hjkl, or just wanna put another prohibited key in insert mode.

Thanks!