To reduce memory consumption by avoiding allocating Ruby objects.

Remove no longer used arguments from the functions.

`a::B = c` should evaluate `a` then `c`. It used to be `c` then `a`. The
`OP_SETMCNST` instruction operands are designed for older order in mind.
Should we changed the operand order?

Fix tree of mruby-bin-example

But `mktime(3)` for the date returns `-1` which happen to be the
error value.

It was caused by #5628.

Toplevel includes the top of the method/class/module definitions.

Fixes file header in src/{cdump,dump}.c [ci skip]

The file headers were pointing to each other's files.

Fixing keyword arguments with `super`

Allows handling of unaligned cptrs for `MRB_NAN_BOXING`

This reverts commit d3b7601a.