Fix typos in the ListWithStat class's set methods

Comparing oldElement to itself will always return true, it is very likely this
was not noticed as this code is only hit when adding a null value, or writing
over a null value in the list.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Fix an infinite loop in ErlangDist::setParams

This method was trying to call the superclass (GammaDist) version that takes a double
argument for the k value.  Add a cast to force it to call the correct method instead
of calling itself.  Could also have been fixed by adding an explicit super to the
call.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Fix the BinaryDataReader constructor that takes an InputStream argument

This would never work as 'in' has not been initialized yet, it very likely meant
to construct the stream based on the inputStream that was given as an argument.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Pull out a seed validation method to avoid repeated code in MRG32k3aL

Also, the incoming seed values must be checked for negative values, add this check.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>