Squashed commit of the following:

commit 99b41a29
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 15 11:04:13 2017 -0600

    apps/system/composite:  Remove configuration settings that are no longer used.

commit 66817949
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 15 09:26:49 2017 -0600

    apps/system/composite:  Restore USB tracing; remove unused field in a structure.

commit 23f1dd5e
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 15 08:58:14 2017 -0600

    system/composite:  Remove CDC/ACM and MSC configuration logic.  This belongs in the OS composite initialization.  Add and argument so that you can select the USB composite configuration to be attached.

commit f8711488
Merge: 00896040 234afcd8
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 14 16:25:48 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit 00896040
Merge: f913ea01 ae1eeada
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Thu Jul 13 13:59:25 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit f913ea01
Merge: bcbdd798 915b42f8
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jul 10 11:08:46 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit bcbdd798
Merge: 2219c02d 1657d1ff
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 7 20:28:30 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit 2219c02d
Merge: fe1e52a8 d81d9c41
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Wed Jul 5 11:12:09 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit fe1e52a8
Merge: 94f82d47 75f29d9d
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jun 30 16:14:36 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit 94f82d47
Merge: a11806ee ffe0640d
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Thu Jun 29 10:19:55 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit a11806ee
Merge: f29dc985 5f5f8878
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jun 26 11:57:00 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit f29dc985
Merge: 70faf0d1 d8759ffe
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jun 19 17:26:00 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit 70faf0d1
Merge: 7d3b1581 a7770590
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jun 16 17:33:46 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit 7d3b1581
Merge: b2c392d4 c8ae5f16
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jun 16 17:30:39 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit b2c392d4
Merge: 95eb2034 f3dc5bea
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jun 5 17:41:02 2017 -0600

    Merge remote-tracking branch 'origin/master' into composite

commit 95eb2034
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jun 2 07:09:44 2017 -0600

    apps/system/composite: Add a configuration option to the boardctl() calls to support multiple composite device configurations dynamically.

commit 7652b678
Author: Frank Benkert <Frank.Benkert@avat.de>
Date:   Thu Jun 1 15:19:40 2017 -0600

    Update to apps/system/compsite assocated with big changes to the composite device logic