SX-1256 Allow shorthands to be overriden

Read the override property of shorthands, use those values and merge them on top of the generated steps

Add the shorthand demo Allows this:

{
"type": "change-input",
"target": "alias#block_1>input#COLOR",
"bannerCopy": "Change this to any color",
"override": {
    "banner": null,
    "tooltips": [{
        "target": "alias#block_1>input#COLOR",
        "position": "right",
        "text": "Me too! I even removed the banner by setting it to `null`"
    }]
}
}

To remove a banner generated by a shorthand and putting in your own challenge data

Coverage summary
Statements	34.36%	2015/5865
Branches	26.76%	209/781
Functions	35.01%	683/1951
Lines	34.21%	1945/5685

KanoComputing / kano-code

SX-1256 Allow shorthands to be overriden #1700