3.0.0-RC1

NOTE: This is the first 3.0.0 release, e.g. it's alpha. We're not guarantee any reliability neither API stability in further versions.

Main features

• This RC removes Promise concurrency types from the library and replace them to modern async/await concurrency mechanism.
• Increased minimal OS version that support by the lib: iOS 13, macOS 10.5 (due to async/await).
• This is the last version which supports Carthage dependency manager, on 3.0.0-RC2 it'll be dropped due to its low prevalence.

What's Changed

• Remove Promises by @pharms-eth in #515
• Update unstable branch with 2.6.1 patch by @yaroslavyaroslav in #541
• Refactor ci/cd pipeline by @yaroslavyaroslav in #545
• update docs for automatic gas. by @yaroslavyaroslav in #556
• Automatic Gas rewrite for unstable branch by @mloit in #559
• Merge master into develop by @yaroslavyaroslav in #562
• develop to unstable by @yaroslavyaroslav in #563

Full Changelog: 2.6.4...3.0.0-RC1