- use iverilog's -gstrict-expr-width throughout test suite
- add warnings for excess bits or padding zeroes in number literals
- add new --oversized-numbers parameter to retain support for unsized
  numbers wider than 32 bits
- localized use of oversized numbers to new truncate test suite which
  verifies the behavior of both modes, and compares against the known
  behavior of iverilog

Workarounds for resolved iverilog issues have been removed.

- pattern keys now represented as TypeOrExpr
- support for simple integer struct pattern keys

- previously the overrides for parameterized data types could only
  reference data declarations at the module scope
- their use within procedures is still allowed, but cannot currently
  refer to localparams declared within procedures
- add procedure scope location accessors to allow scoped traversals to
  mark where injected items will end up in advance

- disallow using end label alone on blocks
- improved parse error for mismatches
- add label checking for non-block constructs
- allow generate block to have label before begin

- general refactoring throughout
- improved metrics for dropping unneeded modules
- fix re-visiting a converted instance in the same pass

- fix type/expr ambiguity for interface and class parameters
- check for parameter kind mismatch up front
- centralize key logic in ResolveBindings

- variable-size string parameter conversion restricted to modules which
  depend on the size of the string parameter
- string localparams are typed as appropriately sized vectors
- remove ordered parameter binding logic from string param conversion

- `expr.name[idx]` considers `expr.name` could be a struct array
- remove fallback struct type lookups which were guaranteed to fail

- fix preservation of loop variables when breaking
- extend Yosys-compatible constant loop conversion to support loop
  variables declared outside of the looop

- avoid premature conversion of default struct type parameters
- allow use of $clog2, $signed, and $unsigned in type parameters
- more thorough and efficient top reference ident renaming
- precede type param conversion with hier const pass