- Backwards Compatibility Breaks:
	- `spawn`'s `stdout` and `stderr` are now Buffers
		- If you're upgrading, all you have to do to get the previous functionality is to do `stdout.toString()`
	- `outputPrefix` value no longer affects `stdout` and `stderr` results (only their output to the terminal)
- Added:
	- `hasSpawnSync`
	- `hasExecSync`
	- `isExecutable(path, opts?, next)`
	- `isExecutableSync(path, opts?, next?)`
	- `spawnSync(command, opts?, next?)`
	- `execSync(command, opts?, next?)`
- Improvements:
	- `exec` now supports `outputPrefix` option
	- The checks to see if an executable path exists and works have been greatly improved and abstracted out from `determineExecPath` into `isExecutable` and `isExecutableSync`
	- `determineExecPath`, `getExecPath`, and `isExecutable` can now operate synchronously with a callback using the `sync: true` option
	- Retrieval and writing to a path cache can now be disabled using the `cache: false` option
- Updated dependencies