Copatterns Implementation

As GitHub does not seem to support milestones on forks, we will proceed with a wiki page.

Here's how I imagine the roadmap for a copatterns implementation:

• Investigate elaborator
• Create a meaningful function definition using existing elaborator constructs
• Parse copatterns
• PTerm copatterns
• Implement elaborated copatterns

1. Implement non-nested copatterns without support for standard pattern matching
2. Implement support for standard pattern matching in copattern clauses
3. Implement nested copatterns (with support for standard pattern matching