Rename "metaData" to "metadata"

[robinmacharg]

Goal

Rename internal occurrences of "metaData" with "metedata" for cross-platform consistency and as a basis for subsequent work. This change leaves alone any occurrences that are destined for the Bugsnag HTTP API since this has not changed. For completeness: If API-related occurrences are changed at a later date they will have to account for both "metaData" and "metadata" validly existing in on-disk events.

Design

Simple manual refactor, file by file, using repeated case-sensitive text search and avoiding API interacting occurrences. One gotcha was the mention in the module.modulemap that caused compilation errors with erroneous root cause.

Changeset

Multiple files affected (not all visible from an XCode full-text search):

M	OSX/module.modulemap
M	Source/Bugsnag.h
M	Source/Bugsnag.m
M	Source/BugsnagBreadcrumb.m
M	Source/BugsnagConfiguration.h
M	Source/BugsnagConfiguration.m
M	Source/BugsnagEvent.h
M	Source/BugsnagEvent.m
M	Source/BugsnagKeys.h
M	Source/BugsnagMetadata.h
M	Source/BugsnagMetadata.m
M	Source/BugsnagNotifier.h
M	Source/BugsnagNotifier.m
M	Tests/BugsnagEventTests.m
M	Tests/BugsnagSinkTests.m
M	iOS/BugsnagTests/BugsnagEventFromKSCrashReportTest.m
M	iOS/module.modulemap
M	tvOS/module.modulemap

Tests

Existing tests were modified for consistency and all passed.

Review

Outstanding Questions

• This pull request is ready for:
  • Initial review of the intended approach, not yet feature complete
  • Structural review of the classes, functions, and properties modified
  • Final review

• The correct target branch has been selected (master for fixes, next for
  features)
• Consistency across platforms for structures or concepts added or modified
• Consistency between the changeset and the goal stated above
• Internal consistency with the rest of the library - is there any overlap between existing interfaces and any which have been added?
• Usage friction - is the proposed change in usage cumbersome or complicated?
• Performance and complexity - are there any cases of unexpected O(n^3) when iterating, recursing, flat mapping, etc?
• Concurrency concerns - if components are accessed asynchronously, what issues will arise
• Thoroughness of added tests and any missing edge cases
• Idiomatic use of the language

[kattrali]

This change leaves external API-related occurrences as they are.

What does this part mean? As in the HTTP public interface or library public interface?

[robinmacharg]

This change leaves external API-related occurrences as they are.

What does this part mean? As in the HTTP public interface or library public interface?

Correct: HTTP. Any occurrences of "metaData" - capital-D - that are sent to the main Bugsnag API have been left as-is. I'll edit the commit message to clarify this.

[kattrali]

The changeset itself looks good, the tests are either failing and/or warning because the Xcode project files for tvOS and macOS (tvOS/Bugsnag.xcodeproj and OSX/Bugsnag.xcodeproj) need to be updated with new filenames.