feat(general): Add new debug image variants

[jan-auer]

This adds new variants for debug images (elf, macho and pe). Since they are structurally equivalent, they all use the same type NativeDebugImage, which is also used by the now legacy symbolic variant. apple is now considered a legacy alias to macho.

Conversion apple -> macho:

Since the Apple type effectively describes MachO, the normalizer now automatically performs a conversion. Note that this discards the cpu_name and cpu_type values, but those are no longer required for symbolication. This is also performed during renormalization.

Renamed properties:

• id -> debug_id (required)
• name -> code_file (required)

New optional properties:

• code_id
• debug_file

[codecov-io]

Codecov Report

Merging #188 into master will increase coverage by 0.33%.
The diff coverage is 89.07%.

@@            Coverage Diff             @@
##           master     #188      +/-   ##
==========================================
+ Coverage   64.81%   65.15%   +0.33%     
==========================================
  Files          83       84       +1     
  Lines        9042     9126      +84     
==========================================
+ Hits         5861     5946      +85     
+ Misses       3181     3180       -1

Impacted Files	Coverage Δ
general/src/store/mod.rs	81.25% <75%> (+2.67%)	⬆️
general/src/protocol/debugmeta.rs	94.63% <89%> (+4.05%)	⬆️
general/src/store/legacy.rs	93.33% <93.33%> (ø)

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[jan-auer]

This is a breaking change (due to the apple -> macho normalization), thus this will be released as 0.5.0.