Document webpack change: Refactor compilation

[webpack-bot]

A pull request by @sokra was merged and maintainers requested a documentation change.

See pull request: webpack/webpack#8017

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• remove origin, dependencies and originLoc from WebpackError, only module is relevant
• remove Semaphore and replace it with AsyncQueue
• add AsyncQueue as Tapable object
• remove Compilation.waitForBuildingFinished
• Merge Compilation.addModuleDependencies into Compilation.processModuleDependencies
• add Compilation.handleModuleCreation
• add Compilation.factorizeModule
• deprecate Module.needRebuild, add Module.needBuild
• remove Module.unbuild
• add Module.invalidateBuild
• improve sorting of errors and warnings
• add integration time (profile) to module stats
• add locations in module trace

What kind of change does this PR introduce?
refactoring

Did you add tests for your changes?
existing test

Does this PR introduce a breaking change?
yes

What needs to be documented once your changes are merged?

• remove origin, dependencies and originLoc from WebpackError, only module is relevant
• remove Compilation.waitForBuildingFinished
• deprecate Module.needRebuild, add Module.needBuild
• remove Module.unbuild
• add Module.invalidateBuild