String formatting using US locale

String formatting using US locale.
Closes issue #102 and PR #100

Migration Guide.

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Pull Request #101

Update Criteo Plugin

Update Criteo Plugin with new events
See doc for more information.
Improved serialization and migration.

Migration Guide.

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Pull Request #93 and #94

Version 4 SDK

Replaced Response Data delegate with Attribution changed delegate
Config objects to launch SDK and track events
Send currency with revenue
Add Partner parameters
Offline mode
Criteo plugin allows to track Criteo type of events
See doc for more information.

Migration Guide.

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Pull Request #90

Target SDK 21

Change Android SDK target to 21, a.k.a, Lollipop

Migration Guide.

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Pull Request #87

Use Context in place of Activity

You can now call the Adjust api with a Context instead of an Activity.
Updated pom.xml for maven

Migration Guide.

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Pull Request #75

SDK plugins

Creation of the plugin mechanism for the SDK.

Migration Guide.

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Pull Request #69 & #70

Use Google Advertisement ID as default device ID

Use Google advertisement ID as default device ID. If Google Play Services is present, don't send MAC Address.
Remove Google Play Services jar. Only the one provided by the app is needed.

Migration Guide.

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Pull Request #63

Deeplink opened after install

Opens deeplink if the server responds with one after the install

Migration Guide.

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Pull Request #58

Fix check malformed app token

Fixed bug that didn't handle malformed app token properly

Migration Guide.

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Pull Request #59

Send tracking_enabled

Send tracking_enabled to know if the user opt-out of tracking
Always sending Google Play Services Advertisement Id
Migration Guide.