add a paragraph about libbsd

fix mp3 length detection without a call to mpg123_scan the length returned by mpg123_length is not necessarly accurate (well, even in that case it's not guaranteed to be exact, i.e. if a file is modified while it's playing.) fixes the length reporting on some mp3 files i had around.

print the current modes after 'amused consume/repeat'

typo in print_status: now it's mode, not repeat

fix 'amused load' with empty playlist it didn't send the IMSG_CTL_COMMIT final message so it would get stuck. This also makes 'amused flush' redundant since it's possible to 'amused load </dev/null'.

delete .d files produced by the tests

add DISTNAME variable like the one from bsd.port.mk, here it's used to decide the name of the tarball.

include contrib/ in the tarball

amused.1: minor tweaks

make the on|off argument to consume/repeat optional

define constants for mode special values and add a toggle value

amused-monitor: fix rounding round() rouds towards infinity, but for the line counting i need a round towards zero, the one provided by int()

amused.1: sort the events

amused-monitor: fix bug when window is taller than playlist adjust the index before reordering the entries, otherwise we may try to read out-of-bound because the reading loop wraps at $lines, not at $tmp size.

amused-monitor: support consume too (s/repeat/mode)