Request for new color tag named "error" for buttons, text etc

Currently we have multiple color tags like `is-link` , `is-success` , `is-warning`  for creating buttons and texts.

Please create a new tag `is-error` just like `is-danger`.

In programming `"success"`, `"error"`, `"warning"`, and `"info"` are most used labels.

The new `is-error` color label will be much more useful in data labeling.
