NuQasm2 v0.31 -- features and bug fixes

NuQasm2 v0.31

• -q flag with -c outputs OPENQASM 2.0 source after unrolling custom gates
• clean up example because nuqasm2 doesn't handle measure q -> c
• fixed bug in file output
• param binding now will pass unbound param text if no param can be bound in unrolling op in gate definition
• created regression test examples
• fixed bug error no space after gate reg list before curly