[Cologne] Prebuilt packages for Mac, Windows and Linux

Codename Cologne has been released. (Aug 8, 2019)

Major updates are

Base Pharo is upgraded to Pharo 7.0.4.
JavaScript library to use ViennaServer or VDMPad to evaluate VDM-SL.
ViennaDoc is a documentation tool to create an animatable and testable documentation.

While Mac and Linux version use 64bits VM, Windows version still use 32 bits version.
Local VDMJ process can be run on Mac, Linux, and Windows.