Release v1.1.0

Dependency updates etc. (#11)

* deps updated

* type hints added & travis php version updated

* [skip ci] phpunit configuration updated for 9.3

* [skip ci] fallback versions reverted & rollback php 7.4 features

Release v.1.0.3

• common package upgraded
• symfony http-foundation package upgraded

Release v.1.0.2

travis updated (#8)

Release v.1.0.1

• packages updated (for security)
• psalm implemention

Release v.1.0.0

• purchase
• authorize
• complete
• cancel
• refund