Enable TPJM5.Calculate and TPJMD5.CalculateFile methods to set buffer size.

[delphidabbler]

Pass an optional BufferSize parameter to each Calculate overloaded method and to CalaculateFile that enables buffer size to be set.

Make default value DefBufferSize (or 0 which is taken as DefBufferSize).

[delphidabbler]

Pass an optional BufferSize parameter to each Calculate overloaded method and to CalaculateFile that enables buffer size to be set.

Overload is only needed for CalculateFile and the TStream overload of Calculate. This is because the methods call a Process method and only the TStream overload of Process and ProcessFile use BufferSize