fixed dtype method for (temporary) Variable representing scalars
added missing import
fixed matching(orderby='EDtM')

it should use floats, not int
change version number (-pre not supported anymore)
fixed optimized_matching(orderby='EDtM')

initialize to a vector of zero instead of a length-1 vector with the length as value
also use float instead of int for the distance
do not transfer the contextual filter to called functions