mcstas2vitess for McStas 2.x -> Vitess 3.x conversion of components

[willend]

On mccode-3:

• to be removed since new code structure is (currently) not compatible

On master:

• move to Legacy-perl-cmdline
• Add patch to call code-generator with full path
• Potentially auto-generate .vif file e.g. for string type inputs etc.

[willend]

Also, a little work is likely needed to get DEPENDENCY system working.