feat: Add dimension selector tool palette at bottom of screen

[aranega]

Closes CC-203

[seankmartin]

This shouldn't be merged until the horizontal tool palettes are available. If the horizontal tool palettes have an issue, an alternative here would be to make three tool palettes with queries, one for each dimension. Like so:

"toolPalettes": {
    "X": {
      "side": "bottom",
      "row": 1,
      "size": 120,
      "query": "dimension:x"
    },
    "Y": {
      "side": "bottom",
      "col": 1,
      "row": 1,
      "size": 120,
      "query": "dimension:y"
    },
    "Z": {
      "side": "bottom",
      "col": 2,
      "row": 1,
      "size": 120,
      "query": "dimension:z"
    }
  }