Windows cmd scripts to change hosts permissions

I created two windows cmd scripts that can work together to change permissions for
the current user to modify the hosts file.

the first script `win-hosts-check.cmd` checks if the permissions on the file are sufficient. It can be called from it's directory.

If not it will call the second script `win-hosts-set.cmd` which will trigger the windows
permission dialog asking for enough rights to midify the permissions on
the hosts file for the current user.

See issue #40

Note 1: As those are supporting files I didin't know where to place them. So I create the `cmd` subdirectory. I don't know the correct convetions for those vagrant plugins with those.

Note 2: The principle on linux if the permissions are not enough is to sudo out a sed command. Those two script are not aligned with such a principle. Instead those work idempotent and the first script only needs to be called as it will take care to set permissions only if necessary.