Merge pull request #39 from clusterpy/development

Maxptabu algorithm now discards candidates the right way
Need to complete tests for all algorithms.
layer: including the possibility of running the random aggregation
maxpTabu: reduced convergence criterion
Merge pull request #40 from JuancaDuque/master

fixed: (1) random cluster and (2) tabu convergence
Add basic test case for maxptabu for size of regions

In a simple case created with constants as the threshold value,
the size of the regions should be greater than the threshold number.
The new test will help to know if the meaning of the threshold and
idea behind threshold works.
Fix seed to fit into Numpy's random range

Ref: https://github.com/numpy/numpy/commit/6b1a1205eac6fe5d162f16155d500765e8bca53c
Merge branch 'development' of github.com:/clusterpy/clusterpy into development