Allow only currencies with price feed when creating offers

[DrColver]

Fix #1739

[axpoems]

I still get the error with stack trace when creating an offer:

Steps to repro: Select market THB > Create offer > Sell Btc > ... and it fails upon arriving in section Price inside the wizard.
I think we also need to apply this in TradeWizardMarketController, see stack trace:

[DrColver]

I couldn't reproduce. Sounds like the price feed might be having troubles.

There is a lot of places where a stack trace is shown if there is an issue with the price. I think it would be better to allow creation of offers even when the price feed doesn't work and handle the price issue separately.

[axpoems]

I couldn't reproduce. Sounds like the price feed might be having troubles.

There is a lot of places where a stack trace is shown if there is an issue with the price. I think it would be better to allow creation of offers even when the price feed doesn't work and handle the price issue separately.

I looked into this more. It fails every time you create an offer and then switch markets and attempt to create a new one there.
The issue was that the price quote was not being reset property. I added the fix for this in #1755.

[axpoems]

ACK

[alvasw]

utACK