PHPC-1329: Remove PHP 7.0 branch in AppVeyor builds

PHP 7.0 was removed from the PHP SDK, likely because the 7.0.x series itself is no longer a supported PHP version.

Author: jmikola

.appveyor.yml

@@ -43,16 +43,6 @@ environment:
       ZTS_STATE: disable
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
       PHP_BUILD_CRT: vc14
-    - PHP_REL: 7.0
-      ARCHITECTURE: x64
-      ZTS_STATE: disable
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
-      PHP_BUILD_CRT: vc14
-    - PHP_REL: 7.0
-      ARCHITECTURE: x86
-      ZTS_STATE: enable
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
-      PHP_BUILD_CRT: vc14
 
 install:
   - .appveyor\install.cmd