Explicit colors for readline and frames

On some terminals readline input after
"em400>" prompt is displayed black on black.

The same applies to the window frames and titles.

This is reproducable using rxvt-unicode on
FreeBSD 11.

Introduce two color pairs, C_FRAME and C_INPUT
and associate window frame attributes with the
(struct awin_t).
Simple .gitignore file
Merge pull request #2 from saper/master

Explicit colors for readline and frames