Update Android Gradle plugin and Wrapper#7

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friederbluemle wants to merge 4 commits intoChainfire:masterfrom friederbluemle:update-project

Commits on Feb 28, 2020

Do not fail with no local.properties
friederbluemle
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Commits on Mar 5, 2020

Update Gradle Wrapper to 5.6.4
friederbluemle
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Commits on Apr 10, 2020