guava v22 and v23 reintroduced java 7 support

[AEtherSurfer]

https://github.com/google/guava/wiki/Release22
https://github.com/google/guava/wiki/Release23
the guava version is tagged with -android but as has been said many times please don't use google-maps-services-java with android.

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[AEtherSurfer]

I signed it!

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[domesticmouse]

Thanks!