cockpit.js: Errors

## cockpit.js: Errors cockpit.js: Errors — Problem codes and messages |

## Problem Codes

Cockpit represents problems with standardized problem string codes.

`"access-denied"` | The user is not permitted to perform the action in question.
`"authentication-failed"` | User authentication failed.
`"internal-error"` | An unexpected internal error without further info. This should not happen during the normal course of operations.
`"no-cockpit"` | The system does not have a compatible version of Cockpit installed or installed properly.
`"no-session"` | Cockpit is not logged in.
`"not-found"` | Something specifically requested was not found, such as a file, executable etc.
`"terminated"` | Something was terminated forcibly, such as a connection, process session, etc.
`"timeout"` | Something timed out.
`"unknown-hostkey"` | The remote host had an unexpected or unknown key.
`"no-forwarding"` | Could not forward authentication credentials to the remote host.

## cockpit.message()

    message = cockpit.message(problem)
    message = cockpit.message(exception)

Return a message for the `exception` or `problem` code passed as an argument. If the argument is an object with a `"message"` property, as is the case with most exceptions, that will be returned directly. If the argument is an object with a `"problem"` property, then it will be used as the problem code. An appropriate message will be returned for problem codes.