API card, proxy tab: Changes to proxy selection drop-down menu

[matleppa]

On API card under tab 'proxy' it is possible to select a proxy to which the API is to be connected.

Problem

Currently the drop-down list contains a list of proxy names. In case the API is not connected to a proxy, the drop-down shows the name of first proxy.

Solution

In order to get the drop-down menu more informative especially in case of multiple proxies, the following matters can be added.

• as the first option, add text "Select one" and set that option as deactive
  • when there is no proxy selected and the drop-down menu is closed (only one line), the text "Select one" is displayed instead of the first proxy name.
• for each option containing proxy name, display also the proxy type

Corrected later: In other places regarding similar functionality the phrase "Select one" is used, so it should be used here also.

[preriasusi]

There's also issue with emq brokers, but that's another issue.

[Nazarah]

assigning myself