Add Length Limit and Axle Weight Limit fields

[arch0345]

Adds fields for maxlength and maxaxleload. Labels match what MUTCD signs use:

Also:

• added these fields to moreFields of appropriate highway presets
• changed maxweight field label to Weight Limit to match MUTCD signage:
  
• swapped maxweight_bridge for maxweight field for Residential Road preset as it's more common for minor roads like these to have a weight limit that's not just at a bridge
• renamed maxheight field to 'Vertical Clearance'
• renamed maxstay field to 'Time Limit'
• renamed maxwidth field to 'Width Limit'

[github-actions]

🍱 Preview the tagging presets of this pull request here: https://pr-911--ideditor-presets-preview.netlify.app/id/dist/#locale=en.

[1ec5]

While you’re at it, this “Max” terminology also appears in the maxwidth field, which could be renamed to avoid abbreviating “maximum”:

id-tagging-schema/data/fields/maxwidth.json

Line 4 in 6fd8dc0

"label": "Max Width",

These are called “Width Limit” or “Width Restriction” in the U.S., though few signs refer to the restriction by a noun.

[1ec5]

Though this term is officially used in the U.S., it may be less familiar to some users who see these signs and think of them as simply “height limits”. Fortunately, schema-builder lets you specify terms for this field that will show up when searching for the field in iD. It’s probably a good idea to add all the previous labels as terms to accommodate existing users’ muscle memory.

[tyrasd]

🤔 there is the distinction between the maximum legally allowed maximum height (maxheight) versus the physical clearance (maxheight:physical). I think the term vertical clearance could be misunderstood to mean the latter of the two…

Why be consistent by continuing the pattern to label all these fields as a “… Limit”, i.e. Height Limit?