Implemented Mission Switch

Squashed commit of the following:

commit 558b6b9ef5d362641f7ffec0eb1ab51513a1cd0a
Author: Friedemann Ludwig <frieludwig@hotmail.com>
Date:   Sun Nov 30 13:49:27 2014 +0100

    Squashed commit of the following:

    commit 4ab89b41ec734be26ae49f6ec9cdfe27be420b91
    Author: Friedemann Ludwig <frieludwig@hotmail.com>
    Date:   Sat Nov 29 18:38:23 2014 +0100

        fixed submodules

    commit bb68597d05cc36993f6018fbae8809718e1554d9
    Merge: b420bab 305a795
    Author: Friedemann Ludwig <frieludwig@hotmail.com>
    Date:   Sat Nov 29 18:31:29 2014 +0100

        Merge branch 'mission_switch' of https://github.com/friekopter/Firmware into mission_switch

        Conflicts:
        	src/modules/commander/commander.cpp

    commit b420babd56e3355033c0264090dd44f77a42a345
    Author: Friedemann Ludwig <frieludwig@hotmail.com>
    Date:   Sat Nov 29 18:27:22 2014 +0100

        added switch once only

    commit 305a7955600a475764e79e06d509aaf25f4ffd7f
    Author: fludwig <frieludwig@hotmail.com>
    Date:   Sat Nov 29 16:45:47 2014 +0100

        removed comment

    commit d98031b59111184ec39dbe1acaa5597e0692e93b
    Author: fludwig <frieludwig@hotmail.com>
    Date:   Fri Nov 28 02:19:39 2014 +0100

        added clear

    commit 64ccbfc648389cf5cf9e98cb09a3762e88baff6f
    Merge: dd38fab 8cc59ca
    Author: Friedemann Ludwig <frieludwig@hotmail.com>
    Date:   Fri Nov 28 00:04:38 2014 +0100

        Merge remote-tracking branch 'upstream/master' into mission_switch

    commit dd38fab17f01351ed6a15d8d78b4afb9ec67b8f6
    Author: fludwig <frieludwig@hotmail.com>
    Date:   Fri Nov 28 00:04:20 2014 +0100

        fixed dataman init

    commit 25c9449e98ea7afef03683ff97aefb770568673a
    Merge: 83e50f6 7cb613b
    Author: Friedemann Ludwig <frieludwig@hotmail.com>
    Date:   Tue Nov 25 13:01:20 2014 +0100

        Merge remote-tracking branch 'upstream/master' into mission_switch

    commit 83e50f67c066469fcbe8b7f3cfa9de25b21c7da7
    Author: fludwig <frieludwig@hotmail.com>
    Date:   Tue Nov 25 13:01:13 2014 +0100

        fixed init

    commit dece62e7d28e1b4b73b9a82eb3ea2eb582fe3d34
    Author: fludwig <frieludwig@hotmail.com>
    Date:   Mon Nov 17 19:51:33 2014 +0100

        fixes for mission switch

    commit a2a04559c1affcd6cb90b4d176609187d85fd44b
    Merge: 2ab12bb 8caada2
    Author: Friedemann Ludwig <frieludwig@hotmail.com>
    Date:   Sun Nov 16 09:53:06 2014 +0100

        Merge remote-tracking branch 'upstream/master' into mission_switch

    commit 2ab12bb890fd32b00d3a116aed8dada996b227e8
    Merge: 8bad1d2 488739c
    Author: Friedemann Ludwig <frieludwig@hotmail.com>
    Date:   Sun Nov 16 09:52:45 2014 +0100

        Merge remote-tracking branch 'upstream/master' into mission_switch

        Conflicts:
        	NuttX

    commit 8bad1d2062a0786bb76f75d35096203a43a252ab
    Author: Friedemann Ludwig <frieludwig@hotmail.com>
    Date:   Wed Nov 12 07:23:58 2014 +0100

        added mission_switch updates from master

    commit 678c3a9695a63a5b5ebe0cfbaba20c29910fd6c6
    Author: fludwig <frieludwig@hotmail.com>
    Date:   Wed Nov 12 06:18:50 2014 +0100

        fixes and more for mission_switch functionality
        Conflicts:

        	src/modules/navigator/mission.cpp

    commit d7c8e2d180b97265bbf7fe963cfd7a9178b86c8e
    Author: fludwig <frieludwig@hotmail.com>
    Date:   Wed Nov 12 06:18:50 2014 +0100

        fixes and more for mission_switch functionality
        Conflicts:

        	src/modules/bottle_drop/bottle_drop.cpp
        	src/modules/commander/commander.cpp
        	src/modules/navigator/mission.cpp

    commit 826678b36e02bd70b41db67a6530f4d54077df71
    Merge: 52e2c84 2f3ffdd
    Author: Friedemann Ludwig <frieludwig@hotmail.com>
    Date:   Wed Nov 12 06:58:22 2014 +0100

        Merge remote-tracking branch 'upstream/master' into mission_switch

        Conflicts:
        	NuttX
        	src/modules/navigator/mission.cpp

    commit 52e2c840d688706ff53504b54134c289faf2e918
    Author: fludwig <frieludwig@hotmail.com>
    Date:   Sun Nov 9 21:43:08 2014 +0100

        implemented mission switch
        Conflicts:

        	src/modules/commander/commander.cpp

         Author:    fludwig <frieludwig@hotmail.com>

         On branch mission_switch
         Changes to be committed:

        	modified:   NuttX
        	modified:   src/modules/commander/commander.cpp
        	modified:   src/modules/dataman/dataman.c
        	modified:   src/modules/dataman/dataman.h
        	modified:   src/modules/mavlink/mavlink_mission.cpp
        	modified:   src/modules/navigator/mission.cpp
        	modified:   src/modules/uORB/topics/mission.h
        	modified:   uavcan

commit 39ecdb9691e4c946d5741f06649afe916b4abe58
Author: fludwig <frieludwig@hotmail.com>
Date:   Sat Nov 29 16:45:47 2014 +0100

    removed comment

commit e36cac7fec045052ba0913d89941c79af56ddf79
Author: fludwig <frieludwig@hotmail.com>
Date:   Fri Nov 28 02:19:39 2014 +0100

    added clear

commit f96c5e970205c8d8509918fb74e931328b4018a9
Author: fludwig <frieludwig@hotmail.com>
Date:   Fri Nov 28 00:04:20 2014 +0100

    fixed dataman init

commit 377851dc8034f49cd9c1bd6ee99840b556ec7fe8
Author: fludwig <frieludwig@hotmail.com>
Date:   Tue Nov 25 13:01:13 2014 +0100

    fixed init

commit d25086758093e23fd5de11d374cdcefc10984412
Author: fludwig <frieludwig@hotmail.com>
Date:   Mon Nov 17 19:51:33 2014 +0100

    fixes for mission switch

commit 2b7fd9bd4de45bfb89103ba95ab7ff53d65f51a4
Author: Friedemann Ludwig <frieludwig@hotmail.com>
Date:   Wed Nov 12 07:23:58 2014 +0100

    added mission_switch updates from master

commit 4057a27960b9bf1cef4d8a094706c53f4f61903e
Author: fludwig <frieludwig@hotmail.com>
Date:   Wed Nov 12 06:18:50 2014 +0100

    fixes and more for mission_switch functionality
    Conflicts:

    	src/modules/navigator/mission.cpp

commit 1c41fb71c59eb80661f5744f39741d985696acd6
Author: fludwig <frieludwig@hotmail.com>
Date:   Wed Nov 12 06:18:50 2014 +0100

    fixes and more for mission_switch functionality
    Conflicts:

    	src/modules/bottle_drop/bottle_drop.cpp
    	src/modules/commander/commander.cpp
    	src/modules/navigator/mission.cpp