Reject invalid string in --date argument
Reject invalid string in --date argument

As parse_date_or_fatal() currently uses atof(), which just returns 0
if the string isn't a valid number, it can never actually be fatal
and will just use "1970-01-01 00:00:00" as the time if the string is
specified wrong.

Fix that by using float() directly so ValueError() is raised.

Signed-off-by: Johannes Berg <8398eb9892c5ab2ff439ca0b5e4b0706dd9ebef9@sipsolutions.net>
[1dc5917c2adeeba13d1ef33dbb40691a1b67cc65@defaultvalue.org: adjust commit summary]
Reviewed-by: Rob Browning <1dc5917c2adeeba13d1ef33dbb40691a1b67cc65@defaultvalue.org>
Tested-by: Rob Browning <1dc5917c2adeeba13d1ef33dbb40691a1b67cc65@defaultvalue.org>

tjanez/bup,gevaerts/bup,pombredanne/bup,tjanez/bup,gevaerts/bup,jbaber/bup,ToxicFrog/bup,pombredanne/bup,tjanez/bup,mhoeher/bup,gevaerts/bup,pombredanne/bup,ToxicFrog/bup,mhoeher/bup,ToxicFrog/bup,mhoeher/bup,tjanez/bup,gevaerts/bup,ToxicFrog/bup,mhoeher/bup,mhoeher/bup,jbaber/bup,pombredanne/bup,gevaerts/bup,tjanez/bup,tjanez/bup,ToxicFrog/bup,pombredanne/bup,jbaber/bup,jbaber/bup,pombredanne/bup,jbaber/bup,mhoeher/bup,jbaber/bup