Align buffers to 32 byte boundaries to allow AVX processing

AVX requires 32 byte alignment, so let's align the buffers accordingly.
extend jack_control to have parameter reset commands
fix alsa driver parameter order

Parameter order doesnt matter for jackd but does for jackdbus. jackd
sets parameters (via Control API) in the order they were specified at
commandline. Thus, the jackd user is expected to specify parameters in
correct order. This is not good solution for jackdbus though. jackdbus
settings persistence in ~/.config/jack/jack.xml stores parameter in
the order they are defined by the driver. OTOH the D-Bus interface
itself suggests no particular order. For example the user can change
only one parameter via the jack_control tool. Other parameters either
have their default values or the ones that were previously set are
used.

The particular ordering problem this changeset aims to fix is that when
user specifies capture/playback device and device, the first one(s)
is/are ignored. This happens because the device parameter is set after
the capture/playback device parameters. The alsa then uses the string
from the device parameter for both capture and playback devices,
despite the user wish to override one or both of them.
Control API: Enforce driver/internal parameter order.

This changeset is required for proper jackdbus handling of
parameters. jackd handling of parameters is improved by making
driver/internal parameters order on commandline irrelevant. E.g.
"jackd -d alsa -d hw:Intel,0 -P hw:Intel,3" should now give same
result as
"jackd -d alsa -P hw:Intel,3 -d hw:Intel,0".

The code used to create the driver parameter list in
jackctl_parameter_set_value(). Apart from the ordering problem,
the old implementation was not properly handling reset of
driver/internal parameters, because upon reset the parameter was not
removed from the set_parameters list which is supplied to
driver/internal.

This commit shifts driver/internal parameter list composition just
before it is needed. I.e master or slave driver open, switch master,
or internal load. The order of parameters is ensured to be the one
defined by the driver/internal.
Make SA_SIGINFO conditional

SA_SIGINFO isn't defined on hurd, so check before setting it.

This patch was used in Debian since 2010-08-01.
Merge branch 'master' into param-order

Conflicts:
	common/JackControlAPI.cpp
Merge pull request #11 from jackaudio/param-order

Enforced driver/internal parameter order
jack_control: fix typo
Alsa audioadapter open file-descriptor leak patch.
alsa driver/adapter improvements to flexibly use playback/capture devices through dbus calls patch.
Merge remote-tracking branch 'upstream/master'
Properly handle empty parameter lists
jack_free() should be used to free memory returned by jack_get_ports()
http://jackaudio.org/files/docs/html/jack_8h.html#a437010097629ac8124a56c752c02f299
Merge pull request #12 from dlahoti/master

jack_free() should be used to free memory returned by jack_return_ports()
jack_server_control patch + getopt_long usage fix.
Make XRun message a bit more explicit.
Devin Anderson patch for Jack/CoreMIDI duplicated messages.
Change framework installation hierarchy for OSX Mountain Lion.
Fix OSX scripts.
Move audioadapter creation code in platform specific part.