rename modules to High.Class, High.Instruction, and so on

[rgrig]

I would like to put all code for the high-level representation of the bytecode in a module High that has submodules Class, Instruction, Field, Attribute, Method, and so on.

At the moment, we have both the old high-level representation (Class, Instruction, Attribute, ....) and the new high-level representation (HighClass and its submodules HighInstruction, HighAttribute, ...) In a few instances I could not understand OCaml's name resolution rules when one has both module A and module B.A, so I think it's a bad idea to have both Instruction and High.Instruction. In other words, the renaming that I propose here should be done only after we get rid of the old high-level representation altogether.

[rgrig]

Related:
#5

[rgrig]

This waits on issue #16.

[rgrig]

I now prefer the following organization.

• LowTypes contains the types for the low-level representation of the bytecode
• HighTypes contains the types for the high-level representation of the bytecode
• Serializer contains functions that read/write thye low-level representation
• Coder contains functions that convert between the low-level and the high-level representations
• other stuff goes in other modules
• keep the user interface small: by default if topl doesn't need it, then don't export it