Video4Linux PR by Ben (dedeibel)

Hello Nico,

improving on PR micro-manager#588 I had some time for more changes on the device. It improves the usability of the device greatly.

There are lot of changed lines in the diff. Here is a list of the performed actions:

    * Adding support for RGB image capturing

    * Allow device path to be configured using a property. Reinit the device if it changes.

    * Allow the resolution to be configured using properties.

    * Used tryioctl function to honor busy state of devices and retry the action.

    * Call v4l2 capability negotiation api to get more detailed error messages in case of
      incompatible devices.

    * Unify logging and leverage errno value of ioctl calls.

    * Move some functions into the device class as they are actually accessing it's state

    * Rearranged functions to follow the call flow better (init, prepare, read, close, ...)

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@16909 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd