Feature: Improved error handling - try { } catch { }?

[blackandred]

Problem to solve: Handling failed steps
Proposed solution: "finally_steps" attribute next to "steps". Finally steps could execute all the time (YAML syntax only)
Other solution to consider: In commandline introduce a symbol to mark tasks that should execute always regardless of result of previous tasks

[blackandred]

What about this? To consider.

steps:
            - "mkdir -p"
            - catch: "%RKD% :slack"
            - catch_all: "..."
            - finally: "%RKD% :cleanup"