This commit adds just enough namespacing to resolve a macro first in the macro's
defining module's namespace (i.e. the module assigned to the `HyASTCompiler`),
then in the namespace/module it's evaluated in. Namespacing is accomplished by
adding a `module` attribute to `HySymbol`, so that `HyExpression`s can be
checked for this definition namespace attribute and their car symbol resolved
per the above.
As well, a couple tests have been added that cover
- the loading of module-level macros
- e.g. that only macros defined in the `require`d module are added
- the AST generated for `require`
- using macros loaded from modules imported via bytecode
- the non-local macro namespace resolution described above
- a `require`d macro that uses a macro `require` exclusively in its
module-level namespace
- and that (second-degree `require`d) macros can reference variables within
their module-level namespaces.
Closeshylang/hy#1268, closeshylang/hy#1650, closeshylang/hy#1416.
010986e8ca