Remove compatibility with PHP<7 and upgrade deps (#124)

* Rm compatibility with PHP<7 and upgrade deps

* Add note about HHVM

* Remove 5.6 and HHVM from Travis testing

* Update web-push-testing-service

.travis.yml

@@ -8,8 +8,6 @@ cache:
     - ~/.selenium-assistant
 
 php:
-  - 5.6
-  - hhvm
   - 7.0
   - 7.1
 
@@ -20,7 +18,7 @@ before_install:
   - nvm install node
 
 install:
-  - npm install web-push-testing-service -g
+  - npm install https://github.com/GoogleChromeLabs/web-push-testing-service -g
 
 before_script:
   - composer install --prefer-source -n

README.md

@@ -9,13 +9,14 @@ the [Web Push protocol](https://tools.ietf.org/html/draft-thomson-webpush-protoc
 As it is standardized, you don't have to worry about what server type it relies on.
 
 ## Requirements
-* PHP 5.6
+* PHP 7.0+
   * gmp
   * mbstring
   * curl
   * openssl
 
-PHP 7.1 is recommended for better performance.
+PHP 7.1+ is recommended for better performance.
+For PHP 5.6 or HHVM compatibility, use the v1.x releases.
 
 ## Installation
 Use [composer](https://getcomposer.org/) to download and install the library and its dependencies.

composer.json

@@ -13,12 +13,12 @@
     }
   ],
   "require": {
-    "php": "^5.6 || ^7.0",
-    "mdanter/ecc": "^0.4.0",
+    "php": "^7.0",
+    "mdanter/ecc": "^0.5.0",
     "lib-openssl": "*",
     "spomky-labs/base64url": "^1.0",
     "spomky-labs/php-aes-gcm": "^1.2",
-    "spomky-labs/jose": "^6.0",
+    "spomky-labs/jose": "^7.0",
     "guzzlehttp/guzzle": "^6.2"
   },
   "require-dev": {