Merge tag 'v1.7.1'

v1.7.1
Improve the ACL matching algorithm

See https://github.com/strongloop/loopback-example-access-control/issues/8
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Merge pull request #214 from strongloop/feature/fix-acl-order

Improve the ACL matching algorithm
Bump version
Merge branch 'release/1.7.2' into production