Yellow triangle warning icon. red stop sign is now error icon
Remove error message in project select area
Remote URL error status uses error icon
Improve remote option warning messages and behavior for #467

* update text when remote value json is empty
* fix detection after form submit of missing values
* fix auto reload of remote values after form submit
Default option value button not always shown

* if the option's allowed values contains the default, don't show the
* default value button