Added plane bounding of the particles

Squashed commit of the following:

commit dcd8045f74f7b0c6d5163c3a5fd63a147ff97fd1
Author: Caskman <eric.cascketta@gmail.com>
Date:   Thu May 2 10:51:07 2013 -0700

    added readme

commit cdf875c08a3fdf93d0ac8416f9cc5aa644f34d6e
Author: Caskman <eric.cascketta@gmail.com>
Date:   Thu May 2 10:48:30 2013 -0700

    fixed bugs

commit d470cf0f9300b88731e9f8c648cbbc8b29ec8053
Author: Caskman <eric.cascketta@gmail.com>
Date:   Thu May 2 10:36:33 2013 -0700

    fixed center positioning

commit 91a41f9f54fcd0354e8036b40f5e41098458c84a
Author: Caskman <eric.cascketta@gmail.com>
Date:   Thu May 2 10:33:12 2013 -0700

    checkpoint

commit 128f7afe21eaa4a9c4b1a38e24ff3e3a56fcd8c7
Author: Caskman <eric.cascketta@gmail.com>
Date:   Thu May 2 10:25:16 2013 -0700

    checkpoint

commit 2ddc705c4cfb6f503016542a853b2f50a8eb7c1f
Author: Caskman <eric.cascketta@gmail.com>
Date:   Thu May 2 08:48:09 2013 -0700

    refactoring

commit 1192ee2fd6bd1dfea4ede8f17b941124fd06c921
Author: Caskman <eric.cascketta@gmail.com>
Date:   Thu May 2 00:37:24 2013 -0700

    Added parameterized boundary control
Gravity and Restitution added

Squashed commit of the following:

commit 884c12bd4521546285b216db678c62360feed2ba
Author: Caskman <eric.cascketta@gmail.com>
Date:   Thu May 2 18:10:07 2013 -0700

    gravity and restitution added