Please add a per-block option to disable code block execution

[hvhaugwitz]

Is your feature request related to a problem? Please describe. I want to ensure that some code blocks are not executable, not even by accident (for example when presenting potentially dangerous commands like rm).

Describe the solution you'd like A per-block option to disable code execution.

Describe alternatives you've considered Not specifying the language prevents execution (error message: Error: could not parse code block) but lacks syntax highlighting.

[vext01]

Related #287

[maaslalani]

Hey this makes sense to me. Perhaps we can include a suffix on the language / code block to avoid execution.