Remove support for PHP 7.0

.travis.yml

@@ -6,7 +6,6 @@ cache:
 install:
   - 'composer install'
 php:
-  - '7.0'
   - '7.1'
   - '7.2'
 script:

README.md

@@ -51,7 +51,7 @@ To start the Heroku deployment process, you can click the button below, please n
 
 ## System Requirements
 * Apache or Nginx webserver
-* PHP 5.6, 7.0, 7.1, 7.2
+* PHP 7.1, 7.2 (Not yet compatible with 7.3.  See issue #422)
   * [GD Graphics Library](http://php.net/manual/en/book.image.php)
 * MySQL or PostgreSQL
 

composer.json

@@ -52,7 +52,7 @@
         }
     ],
     "require": {
-        "php": "~7.0.0 || ~7.1.0 || ~7.2.0",
+        "php": "~7.1.0 || ~7.2.0",
         "ext-pdo": "*",
         "ext-gd": "*",
         "nategood/httpful": "~0.2.20",