Ability to receive any asset with a QR code

**Is your feature request related to a problem? Please describe.**

If clicked "deposit", and chose "BTS", a QR code will show.


However, I can not choose "CNY" or any asset that is not linked to a gateway (e.g. GAT or CNC which were created and only exist on BitShares blockchain).

By the way, should the QR be compatible to [BSIP60](https://github.com/bitshares/bsips/blob/master/bsip-0060.md)?

**Describe the solution you'd like**

A "Receive funds" page, maybe able to input an amount and asset type, an auto-generated reference ID as memo, with a link / QR code compatible to BSIP60. The "funds" word can be "tokens" or "assets" or whatever more appropriate. Please check typical payment apps (e.g. Alipay, Paypal) for prototypes.

**Describe alternatives you've considered**

**Additional context**

Start at the existing Deposit entry point described in the issue and review how the current BTS QR code is generated. Read BSIP60 alongside the proposed Receive funds flow; done means the UI supports receiving arbitrary BitShares assets with an amount, reference memo, and compatible link or QR code.

Written by the indexing model from the issue text.