Update Visa Icon (#216)

* Add updated vaulted visa icon.

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

* Update CHANGELOG.

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

Co-authored-by: Sarah Koop <skoop@paypal.com>

Author: sshropshire

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 * Update android-card-form version to 5.1.0 (fixes #212)
 * Fix null pointer crash in `BaseActivity#shouldRequestThreeDSecureVerification` (fixes #207)
+* Update Visa card icons
 
 ## 5.1.0