blocked_diag_connection_impl
============================

Connects two layers with identical blocked\_representations that use
strength\_patterns.  Equivalent to a special matrix of matrices, in which the
diagonal matrices have diagonal structure and off-diagonal matrices are
zero.  Also equivalent to a blocked\_connection of diag\_connections.  That
is: Matching elements are connected with `excitation`; mismatching elements
in the same block are connected with `inhibtion`; connections between
elements of different blocks have zero connections.

Parameters
----------

	parameter 	default_value
	excitation	1
	inhibition	0