Rename "match" variable in Nyanga's bytecode generator
Separate the statement and expression emit patterns in bytecode generator
Remove unused patterns ListExpression and ParenExpression
Use the FunctionDeclaration node in generated AST

Remove also the "recursive" flag to use instead "locald" to denote
flag local function declarations.
Add proto bytecode method to return primitive code
Add new proto bytecode method "setreg"
Implement Nyanga compiler tests for most common constructs
Optimize registers usage in Nyanga's bytecode generator

Introduce different kind of rules to emit the bytecode. Specialized rules
are given for Statements, Expressions and LogicalExpressions.

The new rules better optimizes registers' usage and produce bytecode
which is often similar or identical to the bytecode generated by LuaJIT.
Fix priority on unary minus in Nyanga parser
Implement concatenate operator as a specific AST entry

Take into account the specificity of the concatenate operator that
requires arguments in contigous slots bytecode generation.
Extend system to keep trace of loops in bytecode generation

Useful to correctly set the jump free register operand in "break"
instructions.
Improve JUMP instruction generation for break statement
Fix error in callmt instruction generation