Update grunt-mocha-istanbul to version 5.0.1 🚀

[greenkeeperio-bot]

Hello 👋

🚀🚀🚀

grunt-mocha-istanbul just published its new version 5.0.1, which is not covered by your current version range.

If this pull request passes your tests you can publish your software with the latest version of grunt-mocha-istanbul – otherwise use this branch to work on adaptions and fixes.

Happy fixing and merging 🌴

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The new version differs by 30 commits .

• b41f2a6 add nonull option, fixes #57
• 3205e3b .babelrc along with instructions
• b883088 add CHANGELOG.md
• fd4b0c5 better errors, need to improve babel test
• 18d551c Merge branch 'master' of github.com:pocesar/grunt-mocha-istanbul
• 47598f2 more in #54, thanks @voxpelli
• b6b5b0e doh
• 0699969 Merge branch 'master' of github.com:pocesar/grunt-mocha-istanbul
• 86881bf grunt 1.0, closes #54
• a29be41 grunt 1.0, closes #54
• 6bd8f40 warn is warning
• deebe93 use defaultOptions in istanbul_check_coverage
• a2b0d91 formatting
• 2039e53 add nodeOptions
• 4cf91ec format

There are 30 commits in total. See the full diff.

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[coveralls]

Coverage remained the same at 100.0% when pulling deb1004 on greenkeeper-grunt-mocha-istanbul-5.0.1 into 59b11dd on master.