add CI job for PHP 8.0 (#69)

Author: eli-darkly

.circleci/config.yml

@@ -9,11 +9,9 @@ workflows:
       - test-with-preinstalled-php:
           name: PHP 7.4
           docker-image: cimg/php:7.4
-      # we currently dont support php 8.0.x due to a bug in php 8 with guzzle, 
-      # this bug is reolved in 8.1-alpha and later
-      #- test-with-preinstalled-php:
-      #    name: PHP 8.0
-      #    docker-image: cimg/php:8.1
+      - test-with-preinstalled-php:
+         name: PHP 8.0
+         docker-image: cimg/php:8.0
 
 jobs:
   test-with-preinstalled-php:

README.md

@@ -10,15 +10,15 @@
 
 ## Supported PHP versions
 
-This version of the LaunchDarkly SDK is compatible with PHP 5.5 and higher.
+This version of the LaunchDarkly SDK is compatible with PHP 7.3 and higher.
 
 ## Getting started
 
-Refer to the [SDK reference guide](https://docs.launchdarkly.com/docs/php-sdk-reference) for instructions on getting started with using the SDK.
+Refer to the [SDK reference guide](https://docs.launchdarkly.com/sdk/server-side/php) for instructions on getting started with using the SDK.
 
 ## Learn more
 
-Check out our [documentation](http://docs.launchdarkly.com) for in-depth instructions on configuring and using LaunchDarkly. You can also head straight to the [complete reference guide for this SDK](http://docs.launchdarkly.com/docs/php-sdk-reference).
+Check out our [documentation](http://docs.launchdarkly.com) for in-depth instructions on configuring and using LaunchDarkly. You can also head straight to the [complete reference guide for this SDK](https://docs.launchdarkly.com/sdk/server-side/php).
 
 The authoritative description of all types, properties, and methods is in the [generated API documentation](http://launchdarkly.github.io/php-server-sdk/).