Passing null/undefined for options crashes node

[alanshaw]

It's legal to pass null/undefined as a value for options. In some instances our API methods expect an options object to exist and try to access properties on it, which fails and crashes the node.

e.g.

js-ipfs/src/core/components/files.js

Lines 279 to 281 in e7d1270

	if (options.hashAlg && options.cidVersion !== 1) {
	options.cidVersion = 1
	}

^^ in this instance, the default assignment only happens if options is undefined so does not work correctly if null is passed.

It could happen if the user is using a ternary to pass/not pass options e.g.

const hashAlg = 'sha2-512' // Obtained from user input perhaps
await ipfs.files.add(Buffer.from('data'), hashAlg ? { hashAlg } : null)`