Remove default comments and references to minp

Add a method that will contain the add to canvas functionality.
Move the algorithm logic to a Worker

The worker will run the algorithm in a Thread on the background.
This will work to get issue #3 done.
Fix Syntax error
Remove non implemented code about the minp

The min-p is an algorithm that will be added, but is not ready yet
for the plugin.
Making the maxp dialog responsible of the run

The algorithm dialog is now responsible of running the algorithm and
presenting the results.
This is now done in a background thread to assure a responsive UI
(closes #3).

 * A few things missing, first is the progress bar
 * A way to cancel the execution cleanly.
Remove Broker

The algorithm dialog now takes on all responsibilities that the Broker
had.

 * Change style of initializer
Merge pull request #4 from sergiobuj/nonblocking

Nonblocking