Drop Task Library

[p3ck]

We will drop the task library when migrating to python3

When discussing the effort needed to move beaker to python3 we discussed beakers strengths and weaknesses. The task library has been one of the biggest. This and the corresponding results reporting has been the source of most of beakers scaling issues.

We will still track installation progress and installation related logs.

Discussion is needed about how we will handle broken installs (watchdog?) and if systems should automatically return to the available pool after a pre-defined time frame.