Batch TemporalMaxPooling

This PR : 
 * adds Batch (3D input tensor) functionality to TemporalMaxPooling;
 * adds doc for TemporalMaxPooling;
 * adds units tests for TemporalMaxPooling;
 * fixes some documentation for TemporalConvolution (output axes were in wrong order);
 * fixes some documentation for LookupTable (output axes were in wrong order).

A lot of the Temporal* documentation has mistakes concerning the specified output axes. For example, the doc says that the output of Temporal/LookupTable modules should be of size `nOutputFrameSize x nOutputFrame`, when the module actually outputs tensors of shape `nOutputFrame x nOutputFrameSize`. I fill send another PR fixing these shortly.