[Libbt-devel] added header files that will be installed

[Alien <ali...@us...>]

I added 2 header files that'll be installed together with the library.

these are the header files that'll have to be used by the frontend to contr=
ol=20
the library.

ALSO!: these header files MUST be used by the library itself as well, so no=
=20
future conflicts arise!
=2D-=20
Alien is my name and head-biting is my game.