* (Babylon) Fall back to non-strict mode
This makes Prettier a little less opinionated about linting. For
example, the following can now be formatted:
```js
function f(a,a){return a}
```
whereas before it would cause an error:
stdin: SyntaxError: Argument name clash in strict mode (1:13)
> 1 | function f(a,a){return a}
| ^
This also allows octal numbers to be parsed,
and therefore fixes https://github.com/prettier/prettier/issues/228
If the code parses neither as strict nor as non-strict, the error from the
strict parse is thrown (as it was before this change).
---
I noticed this while trying out [eslump] with prettier:
eslump | pbcopy; pbpaste | prettier
[eslump]: https://github.com/lydell/eslump
* Add missing test
* Use Object.assign() instead of mutating object
Joseph Frazier