Merge #998

998: Parse macro expansion properly r=CohenArthur a=CohenArthur

This PR adds a base for trying to parse statements or items in macro invocations. We are now able to parse multiple items / expressions / statements properly, but do not lower them properly, which is the last remaining task in #943 

New macro parsing logic:
```mermaid
flowchart TD;
    has_semi -- Yes --> stmt;
    has_semi -- No --> invocation;
    invocation -- Is Parens --> expr;
    invocation -- Is Square --> expr;
    invocation -- Is Curly --> stmt;
```

Closes #943 
Closes #959 
Closes #952 

Co-authored-by: Arthur Cohen <arthur.cohen@embecosm.com>

0 files changed, 0 insertions, 0 deletions