Add support for more kinds of assets.

[johanley]

Supporting more kinds of assets is important, but usually not easy.

Assets I have in mind:

• ETFs
• Bonds
• Mutual Funds

Plain bonds would likely be the simplest to implement of the these three. Plain bonds apparently have high commissions at moderate levels of principal.

One aspect is how widely held the asset is. For example, do people hold actual bonds more than they hold bond ETFs? I don't know.

Another aspect is the tax implications, especially for the non-registered account. Would it be acceptable, at least initially, to restrict an asset class to the TFSA and RIF, and exclude it from the NRA? That would greatly simplify the tax treatment.

Would it be acceptable to support ETFs, but leave out Mutual Funds? The distributions of mutual funds seem particularly complex for tax implications, because they come in a mix of dividends, interest, capital gain, and return-of-capital.

Ref: https://www.finiki.org/wiki/Conventional_bonds