Fix v8 generator to use a non clashing name for built-in 'equals' method.
Clean up in `javascripttypemaps.swg`.

- following the same layout/order as pytypemaps
- added typemaps for `long long` and `unsigned long long`, which are
  only copies of those for `long` and `unsigned long` and hence are
  just experimental.
Redefined set of Javascript smoke tests.
Some fixes for the Javascript generator.

- added missing `exception.i`
- added missing generator block `wrappers` for v8
Added two more Javascript tests.

- `abstract_inherit`
- `char_strings`
Add support for PackedData to Javascript generator.