Use security name for symbol if there is no symbol

[boxydog]

Addresses #100

[boxydog]

Probably this also needs to bump the version number? I wasn't sure. Sometimes maintainers bump it themselves because only they know what order PRs are merged in.

[boxydog]

One downside of this approach is that later clients don't know that the data didn't have a stock symbol.

An alternate approach would be to keep "symbol" empty, but have a property like "key" that is used in place of symbol, where "key" is "symbol, or name if symbol is empty". That would preserve the information that a security has no symbol for later use by clients.

Let me know your thoughts.

[isaacharrisholt]

This is good, thanks. I'm probably going to wait for #105 to be merged first though - that may have an impact on this and I don't wanna be chasing down bugs.

As for the key approach, it's not part of the spec so I'm not too keen to add it if it's not needed. I think this is fine for now. One potential future improvement to quiffen is the concept of strict vs lenient modes. I'll open an issue to remind myself.

[isaacharrisholt]

Worth rebasing this one and re-running the tests since the UV changes

[boxydog]

rebased