Added an MLP guide init file

doc/guide_mlp.rst

+.. py:currentmodule:: bob.learn.pytorch
+
+=============================
+Multilayer perceptron
+=============================
+
+
+Multilayer perceptron training
+===========================================================
+
+This section introduces a work-flow for training a Multilayer perceptron (MLP). Training details, as well as the structure of the MLP are identical to the ones introduced the following publication [NGM19]_. It is recommended to check the publication for better understanding of the below discussions.
+
+

doc/index.rst

@@ -16,6 +16,8 @@ Users Guide
    guide_dcgan.rst
    guide_conditionalgan.rst
    guide_conv_autoencoder.rst
+   guide_mlp.rst
+
 
 ================
 Reference Manual