Added a HUD that shows water and temperature. These values change over time.

Squashed commit of the following:

commit 8e61b65cd91681f418e45dbde5b0a50f87802d8c
Author: Nicolai Czempin <nicolai.czempin@gmail.com>
Date:   Sun Apr 20 02:03:55 2014 +0200

    water expenditure changes with temperature

commit 753c98d1ae20eebf46e59f97138aea5482527603
Author: Nicolai Czempin <nicolai.czempin@gmail.com>
Date:   Sun Apr 20 01:58:41 2014 +0200

    colour the temperature according to "good", "too hot", "too cold"

commit ed4819aad574adb636a95d8a8bdfd0c7cea8101b
Author: Nicolai Czempin <nicolai.czempin@gmail.com>
Date:   Sun Apr 20 01:44:25 2014 +0200

    just ramp the temperature up and down

commit 420ea2e2c8fa9936c2006d845579213f5b4e1060
Author: Nicolai Czempin <nicolai.czempin@gmail.com>
Date:   Sun Apr 20 01:38:45 2014 +0200

    encapsulate active pawn in world method

commit 688529c0948165453662a7ce32503a1ea6f3df71
Author: Nicolai Czempin <nicolai.czempin@gmail.com>
Date:   Sun Apr 20 01:36:27 2014 +0200

    show temperature

commit 31abf826f9232090682747b83399a29a6a11cc65
Author: Nicolai Czempin <nicolai.czempin@gmail.com>
Date:   Sun Apr 20 01:04:47 2014 +0200

    update and show water level

commit b96abcf2664952b4edc1a98fd778aed909b6b3d2
Merge: 5f31cf5 545ff52
Author: Nicolai Czempin <nicolai.czempin@gmail.com>
Date:   Sun Apr 20 00:59:24 2014 +0200

    Merge branch 'feature/HUD' into feature/behaviour

commit 5f31cf523d4d5f88952eb0bd1a8c71b65088f9da
Author: Nicolai Czempin <nicolai.czempin@gmail.com>
Date:   Sun Apr 20 00:59:10 2014 +0200

    prepare using some pawn attributes

commit 545ff52003b0d51808524fbaf1a8423082f080db
Author: Nicolai Czempin <nicolai.czempin@gmail.com>
Date:   Sun Apr 20 00:44:32 2014 +0200

    show water level
Merge branch 'master' of https://github.com/nczempin/lizard-journey