overlappinghighway linter improvements

[srividyacb]

From https://github.com/osmlab/osmlint/issues/271

Reworked on overlapHighway linter to output the overlapping LineString instead of Point/MultiPoint. Here is the sample output.

Now the output is having the linter type and the overlapping highway type in the metadata.

@maning Can you give it a spin on a QA-Tiles extract and verify if its working as expected ?

cc @Ramshackle-Jamathon

[srividyacb]

Updated the bug of adding _fromWay, toWay and overlapping _type to the output featureCollection. New [sample-output] (https://gist.github.com/srividyacb/9dba1fc883aa8704b70409517a066891) after the bug fixes.

@Ramshackle-Jamathon - There are few duplicates for highway if they are any overlapping and selfIntersecting highway together. Need to find a way to remove them.

cc @maning

[Ramshackle-Jamathon]

@srividyacb could we add a flag to have overlapping ignore selfIntersecting Highways?

[srividyacb]

Per voice with @maning - duplicates are less compared to the real errors thrown and we can ignore them.

But there are issues with how linter _type, fromWay and toWay are assigned to the output. Tried debugging but not able to find why they are incorrect sometimes. @Ramshackle-Jamathon can you see if you can find any bug here ?