move tests to subdir
break out util.c into it's own temporary library

to make testing easier
move includes around in an attempt to include less
add beginnings of a second test
basic test for get_user_cfgfile_path()
test other case in get_user_cfgfile_path()
some tests of loading chalresp state
add stdlib.h
re-add libyubikey, needed.
remove some warnings from the new test.
close the tmpfile when done..
use constants
move check_user_token() to util

for testability..
make argv const to get rid of warning
add test for check_user_token()