Merge pull request #1595 from OneSignal/rel/5.2.15 Release 5.2.15

Merge pull request #1584 from OneSignal/release/5.4.0-alpha-01 Release 5.4.0-alpha-01

Merge pull request #1578 from OneSignal/rel/5.3.0-beta-02 Release 5.3.0-beta-02

Merge pull request #1574 from OneSignal/rel/5.2.14 Release 5.2.14

Merge pull request #1569 from OneSignal/rel/5.2.13 Release 5.2.13

Merge pull request #1567 from OneSignal/rel/5.2.12 Release 5.2.12

Merge pull request #1557 from OneSignal/rel/5.2.11 Release 5.2.11

Merge pull request #1544 from OneSignal/rel/5.2.10 Release 5.2.10

Merge pull request #1529 from OneSignal/rel/5.2.9 Release 5.2.9

Merge pull request #1520 from OneSignal/rel/5.2.8 Release 5.2.8