Update @material-ui/core to the latest version 🚀

[greenkeeper[bot]]

The dependency @material-ui/core was updated from 3.0.0 to 3.1.0.

This version is not covered by your current version range.

If you don’t accept this pull request, your project will work just like it did before. However, you might be missing out on a bunch of new features, fixes and/or performance improvements from the dependency update.

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Your Greenkeeper bot :palm_tree:

[greenkeeper[bot]]

• The dependency @material-ui/core was updated from 3.0.0 to 3.1.1.

Update to this version instead 🚀

Release Notes for v3.1.1

Sep 24, 2018

Big thanks to the 21 contributors who made this release possible!
It contains many bug fixes 🐛 and documentation improvements 📝.

@material-ui/core@v3.1.1

• [TextField] Fix alignment bug in Safari (#12906) @shcherbyakdev
• [InputLabel] Fix Chrome's autofill (#12926) @PutziSan
• [Tooltip] Fix unwanted tooltip opening (#12929) @ayubov
• [TextField] Fix RTL support of outlined (#12939) @RobertPurcea
• [Button] Make the outlined button border grey when disabled (#12933) @dispix
• [RootRef] Keep track of the DOM node changes (#12953) @oliviertassinari
• [Grid] Fix rounding errors (#12952) @RobertPurcea
• [Tooltip] Back to 100% test coverage (#12954) @oliviertassinari
• [SwipableDrawer] Don't break when backdrop is null (#12969) @spirosikmd
• [InputAdornment] Fix flexbox alignment bug for IE (#12975) @oliviertassinari
• [FilledInput] Update the background color to match the spec (#12977) @adeelibr
• [ListItem] Fix background color bug on mobile (#12976) @ryusaka

@material-ui/lab@v3.0.0-alpha.17

• [Slider] Remove touchend event listener (#12923) @brian-growratio
• [SpeedDialAction] Add missing TypeScript property (#12959) @KarimFereidooni

Docs

• [docs] Make jss insertion point reference the same as html comment (#12896) @emattias
• [docs] Small fixes (#12904) @oliviertassinari
• [docs] Add reference to material-ui-theme-editor (#12888) @jdrouet
• [docs] Add another case to check when SSR fails (#12908) @oliviertassinari
• [docs] Correct misspelling (dasboard => dashboard) (#12910) @seishan
• [docs] Use core package for (peer-)dependency badges (#12911) @eps1lon
• [docs] Display the backers avatars correctly (3057f97) @oliviertassinari
• [docs] Update themes.md (#12942) @brucegl
• [docs] Fix documentation error in (#12955) @lukePeavey
• [docs] Minor style update of the tabs demos (#12958) @dotku
• [docs] Glamorous is deprecated for emotion (#12963) @oliviertassinari
• [docs] Add Emotion to style interoperability guide (#12966) @lukePeavey
• [docs] Fix IconButton Snackbar demos (#12964) @bhalahariharan
• [docs] Show how to combine OutlinedInput and FilledInput (#12968) @oliviertassinari
• [docs] Fix Typo in PaymentForm.js (#12971) @n3n
• [docs] Fix Typo in page-layout-examples (#12974) @n3n

Core

• [typescript] Improve definitions with strictNullChecks disabled (#12895) @eps1lon
• [typescript] Remove unused isMuiComponent definition (#12903) @eps1lon
• [core] Add setRef helper (#12901) @eps1lon
• [core] Fix umd bundle (#12905) @oliviertassinari
• [core] Use .browserlistrc as single point of thruth for target env §#12912) @eps1lon
• [typescript] Add missing MuiFilledInput to 'Overrides' (#12938) @marcel-ernst