Avoid using deprecated/UNSAFE_* React methods

[BPScott]

React has deprecated its use of a selection of lifecycle methods it has deemed to be unsafe.

The componentWillMount, componentWillReceiveProps and componentWillUpdate lifecycle methods have the potential to cause headaches and We should use the newer, more stable lifecycle methods of getDerivedStateFromProps and getSnapshotBeforeUpdate instead.

We could shuffle onto using UNSAFE_componentWillMount etc but that doesn't fix the root problem.

The good news is ESLint now warns about our usage of these methods so we no longer have to think about this when doing PR reviews, however there are still a few places in existing code where they are used. Any existing use of these functions should be removed

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Search the codebase for react/no-deprecated and refactor the usage of the componentWillMount, componentWillReceiveProps and componentWillUpdate to use the new lifecycle functions.

As of 2018-10-04, searching the codebase for react/no-deprecated shows the following Components are affected:

• AppProvider
• Collapsible (WIP: @dleroux )
• FileUpload (pr [FileUpload] Remove outdated lifecycle methods and fix issue with stale state #1233)
• EventListener
• OptionList
• PositionedOverlay
• ResourceList
• Tabs
• TextField
• ThemeProvider

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[BPScott]

Following an update to eslint-plugin-react in jsx-eslint/eslint-plugin-react#2069 componentWillMount, componentWillReceiveProps and componentWillUpdate will not trigger a react/no-deprecated warning as they are considered legacy componenets but they're not officially deprecated just yet.

We should still move away from them.

[BPScott]

Enabling react/no-unsafe with checkAliases: true option shall complain if we try and use and of the unsafe lifecycle methods, including the unprefixed versions