Extend Example with ability to edit waypoints

[S2Ler]

• Extends Example app with ability to edit waypoints and caches them to disk.
• Moves Example app out of Carthage project.
• Updates Example app with SPM based dependency management.
• Adds localizedDescription to DirectionsError.swift. Without it, Xcode shows runtime issue saying that localizedDescription isn't available.
• Works with Mac Catalyst.
• A lot of room for further improvements :)

[S2Ler]

Unfortunately, current approach with SwiftUI didn't payed out. Need to find another implementation which won't crash.

[S2Ler]

Given that DirectionsPlayground(Former Example) app is separate project, we can bring back integration with Maps for better visualisation.

[codecov-commenter]

Codecov Report

Merging #566 (ed5e46e) into main (bb9fe98) will decrease coverage by 0.07%. The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main     #566      +/-   ##
==========================================
- Coverage   85.30%   85.22%   -0.08%     
==========================================
  Files          52       52              
  Lines        4545     4549       +4     
==========================================
  Hits         3877     3877              
- Misses        668      672       +4     

Impacted Files	Coverage Δ
Sources/MapboxDirections/DirectionsError.swift	83.07% <0.00%> (-2.64%)	:arrow_down:

[kried]

It is a great idea to rewrite the example to use SPM and SwiftUI!

[S2Ler]

New example still not in a good shape. Editing query is buggy.