feat: adjust index builder metadata names and values

Problem

A few new columns have been added to the Google sheet to support the Index Builder

Fixes #136

WeightsSliders sometimes appear below the HelperText (should be to the right)

feat: added ibEnabled / ibIgnoreZero / ibDefaultDirectionality / ibExplanation in source data sheet (with comments for descriptions of each new column)
feat: adjusted code references: scaling -> ibDefaultDirectionality, ignore_0 -> ibIgnoreZero
feat: added support for ibEnabled - this flag will hide indicators ONLY on the Index Builder
feat: added new column ibExplanation to data sheet - this is not yet used by the UI, but we could use this to provide variable-specific context to the user in the UI
fix: remove original source data for scaling / ignore_0 from data sheet
fix: set WeightsSliders so that it does not appear below the HelperText - it should now only appear to the right
fix: temporarily set active=FALSE on Heat Index (Average) - this will help us showcase the new Heat Index (Maximum)
fix: change back to quantile bins, display 6 bins instead of 4

Navigate to https://deploy-preview-141--chicago-env-explorer.netlify.app/builder
- You should see that "Displacement Pressure" and other variables where ibEnabled=FALSE do not appear in this list
Select 1 or more indicators and click Next
- You should be brought to the "Choose Weights" page
- You should see that the sliders only appear to the right, and not below the HelperText
Zoom in a few times with your browser (Cmd + for Mac, Ctrl + for Windows)
- You should see that the sliders only appear to the right, and not below the HelperText
Select weights using the sliders and click Next again
Verify that values for ibDefaultDirectionality properly affect the mapped index data

Name	Link
Latest commit	10cb04a66320d0f3280d670ffd7c604dde303cfa
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