Update to require PHP 7.1+

Hello `3.x` development branch

Once this PR is merged, we can start working on the new [v3.0.0
milestone](https://github.com/re...

Run tests on PHP 8.3 and update test suite

Update test suite and report failed assertions

Test on PHP 8.2

With PHP 8.2 coming out later this year, we should be reading for it's release to ensure all out...

chore(docs): remove leading dollar sign

Fix legacy HHVM build by downgrading Composer

Add badge to show number of project installations

Support PHP 8.1

Use GitHub actions for continuous integration (CI)

Bye bye Travis CI, you've served us well.

Align DocBlock Promise return types

Currently most of the docblocks provide a return type inside the
PromiseInterface like bool or a...

Update PHPUnit configuration schema for PHPUnit 9.3

Add full core team to the license

Added the full core team in order of joining the team

Run tests on PHPUnit 9, run tests on PHP 7.4, simplify test matrix and clean up test suite

Forward compatibility with react/promise 3

Add .gitattributes to exclude dev files from exports

[RFC] Use arrays instead of iterable for multiple cache items

Documentation for TTL precision with millisecond accuracy or below

Using arrays makes the API slightly stricter and allows consumers to
consistently rely on associ...

Use high-resolution timer for cache TTL on PHP 7.3+

Allow legacy HHVM to fail in Travis CI config

HHVM decided to drop support for PHP, so it's questionable if supporting
it in the future is wor...

Improve documentation

Add support for getMultiple(), setMultiple(), deleteMultiple(), clear() and has() (inspired by P...

Prefix all global functions calls with \ to skip the look up and resolve process and go straight...

Rename remove() to delete() for consistency with PSR-16

Add cache expiration support (TTL)

Add $default to return instead of null on cache miss for get()

Simple LRU implementation for ArrayCache

Return Promise for set and remove

Cache miss resolves with null value

Describe current behavior on the cache interface

Forward compatibility with PHPUnit 5 and PHPUnit 6

Add PHPUnit 4.8 to require-dev

Improve documentation

Fix autoload paths

Consistent reporting of test failures and conciser test setup

[RFC] Improve compatibility with legacy versions

Test against PHP7

Adding Code Climate badge to readme

Show test coverage directly after running test