irssi: Update to version 0.8.17.

Signed-off-by: Rudá Moura <ruda.moura@gmail.com>
Adopt fltk to Rudix.

Signed-off-by: Rudá Moura <ruda.moura@gmail.com>
htmldoc: Update to version 1.8.28 + fltk.

Update to version 1.8.28
Build with (static) FLTK.

Signed-off-by: Rudá Moura <ruda.moura@gmail.com>