Moose (Fame?) specific pragmas should have a Moose (Fame?) prefix

[NicolasAnquetil]

Like <FMComment: >, <FMClass:super: >, <FMProperty:type: >, and <FMProperty:type:opposite: >

This would make it easier to search for them and be sure it does not collide with other pragmas from other packages

• <container> could be <FMContainer> (this one looks like it could be used in other packages for other means)
• <source> / <target> could be <FMSource> / <FMTarget>
• <derived> could be <FMDerived>
• <multivalued>
• <navigation: ...>
• <package:>
• <abstract> (in #annotation methods, not sure whether this is for Pharo or Moose)
• <mooseGroup> (related to Moose but not Famix, should we have two prefixes or put Moose everywhere even for Fame ?)