Add boolean member to Perceptron to allow model initialization.
This is useful to show that the perceptron converges to different
solutions depending on initial values of w and bias.
Perceptron graphical example.
For the same data, the solution is different depending on initial values
of w and bias
Switched the unit test for any neighborhood preserving DR method from testing Locally Linear Embedding method to testing Isomap (since LLE seems to be not very robust to noise).
Fixed missing #include's in test Isomap_unittest.cc.
Merge pull request #1016 from vladislav-horbatiuk/lleTest-fix

Switched the unit test for any neighborhood preserving DR method from sting Locally Linear Embedding method to testing Isomap.
Setters/getters in structured machines.
They are required to implement SO-SVMs from interfaces.
Merge pull request #1012 from iglesias/feature/improve_structure

Setters/getters in structured machines.
More debug information for python_modular integration tests
Merge pull request #1007 from iglesias/feature/custom_init_perceptron

Add small functionality to perceptron and graphical example
Merge pull request #1015 from vladislav-horbatiuk/vgorbati-develop

Added a wrapper for t-SNE method implemented in tapkee library and a basic unit test for it.
Added a wrapper for the t-SNE DR method; added an integration test for it (black-listed for now).