read las metadata into file

[unitycoder]

could have optional checkbox, for: read metadata,
and then save into meta.json or meta.txt

• read all metadata available
• save into dictionary or json, or just string separated array
• in viewer, add method to read/query available metadata (if exists in file)

[unitycoder]

this is already available, with arg: -metadata=true

it will read LAS header metadata into "output filename".json

can also get metadata only (without processing clouds)
adding this arg (with previous arg) : -metadataonly=true