Fix man page and usage()

Man page was repeating -f option, the second time instead of -i,
and this option was lost in usage() message. This patch also indent
the output of usage().
Simplify README

The term 'virtual terminal emulator' was broken. There is nothing
virtual about it, it's a terminal emulator.

Signed-off-by: Alexander Huemer <alexander.huemer@xx.vu>
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
added .gitignore file
symlinked config.def.h to config.h
initial commit of my config.def.h
default font is now DejaVu Sans Mono for Powerline