V4 Migration Guide (#500)
V4 Migration Guide (#500)

* Pull migration guide from original v4_migration_guide branch.

* Rename migration guide to mention v4.

* Implement amex section.

* Add migration guide for Card feature.

* Add ellipses to migration guide.

* Revert "Add ellipses to migration guide."

This reverts commit b6a17ae7a0f9da1ed115e927cf2c2cb19f403e44.

* Implement migration guide for LocalPaymentClient.

* Implement GooglePay migration guide.

* Implement PayPalClient migration guide.

* Fix table of contents on migration guide.

* Remove Samsung docs from v4 migration guide.

* Implement VisaCheckout migration guide.

* Add UnionPayClient to migration guide.

* Implement VenmoClient in migration guide.

* Implement 3DS migration guide.

* Add onNewIntent methods to migration guide where appropriate.

* Remove unecessary TODO's.

* Update VisaCheckoutClient migration guide.

* Update v4_MIGRATION_GUIDE.md

Co-authored-by: sestevens <40e0c00ea33d9a847173fa91d68d8fb0da6ba4d6@getbraintree.com>

* Fix version number typo

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Update v4_MIGRATION_GUIDE.md

Co-authored-by: sestevens <40e0c00ea33d9a847173fa91d68d8fb0da6ba4d6@getbraintree.com>

* Update v4_MIGRATION_GUIDE.md

Co-authored-by: sestevens <40e0c00ea33d9a847173fa91d68d8fb0da6ba4d6@getbraintree.com>

* Update v4_MIGRATION_GUIDE.md

Co-authored-by: sestevens <40e0c00ea33d9a847173fa91d68d8fb0da6ba4d6@getbraintree.com>

* Update v4_MIGRATION_GUIDE.md

Co-authored-by: sestevens <40e0c00ea33d9a847173fa91d68d8fb0da6ba4d6@getbraintree.com>

* Apply suggestions from code review

Co-authored-by: sestevens <40e0c00ea33d9a847173fa91d68d8fb0da6ba4d6@getbraintree.com>

* Add try catch around BraintreeClient instantiation

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Fixup amex snippet

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Fixup card snippet

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Fixup google pay snippet

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Fixup PayPal snippet

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Fixup VisaCheckout snippet

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Fixup union pay snippet

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Fixup ThreeDSecure snippet

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Add clarifying comment for gradle changes

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Fix migration guide wording

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Fix broken link

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Add browser switch section

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Fix code typo

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Add docs for DataCollector

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Update v4_MIGRATION_GUIDE.md

Co-authored-by: sestevens <40e0c00ea33d9a847173fa91d68d8fb0da6ba4d6@getbraintree.com>

* Update v4_MIGRATION_GUIDE.md

Co-authored-by: sestevens <40e0c00ea33d9a847173fa91d68d8fb0da6ba4d6@getbraintree.com>

* Add 3D Secure lookup example to migration guide.

Signed-off-by: Steven Shropshire <e0eaefab33cb0c3d300c8879d154a2846a56c9dd@getbraintree.com>

* Add check for multiple request codes to code snippets

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Add explicit section on implementing multiple payment methods

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

* Fix typo

Signed-off-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>

Co-authored-by: Steven <d7de9234e838633877a6b1d32b8d5dd4afe6d601@paypal.com>
Co-authored-by: Sarah Koop <3ae9c22a3976e9d9421c1637f587b5316b2fe004@paypal.com>
Co-authored-by: sestevens <40e0c00ea33d9a847173fa91d68d8fb0da6ba4d6@getbraintree.com>
braintree/braintree_android,braintree/braintree_android,braintree/braintree_android,braintree/braintree_android