Xamarin bindings

Small changes to adapt to Xamarin bindings

Migration Guide.

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Pull Request #108

Prefix sociomantic params

Prefix sociomantic params to avoid ambiguities
Remove warning missing iAd
Send empty receipts
Updated criteo plugin

Migration Guide.

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Pull Request #99 #101

Fix warning issues

Removed XCode warnings issue #96
Fixed SWIFT issue #74
Framework and static library build fix
Added default tracker

Migration Guide.

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Pull Request #98

Clean Json parsing

Prevents possible exception on json parsing

Migration Guide.

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Pull Request #97

Click label in attributions

Added the click label parameter for attributions.

Migration Guide.

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Pull Request #94

Sociomantic plugin

Sociomantic plugin allows to track Sociomantic type of events.
See doc for more information.
Added framework target with support to all architectures

Migration Guide.

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Pull Request #91

Receipt validation

In-app-purchase receipt validation.
See our Readme for more information.

Migration Guide.

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Pull Request #89

Update Criteo Plugin

Update Criteo Plugin with new events
See doc for more information.

Migration Guide.

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Pull Request #87

Criteo plugin

Criteo plugin allows to track Criteo type of events.
See doc for more information.

Migration Guide.

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Pull Request #80 #84

Fix attribution clicks

Fix deeplink attribution
Fix iad attribution

Migration Guide.

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Pull Request #78