Add ext yac (#407)

* add ext yac

* enable yac for windows

* enable yac test for windows

* correct

config/ext.json

@@ -623,6 +623,14 @@
             "dom"
         ]
     },
+    "yac": {
+        "type": "external",
+        "source": "yac",
+        "arg-type-unix": "custom",
+        "ext-depends-unix": [
+            "igbinary"
+        ]
+    },
     "yaml": {
         "type": "external",
         "source": "yaml",

config/source.json

@@ -673,6 +673,16 @@
             "path": "COPYING"
         }
     },
+    "yac": {
+        "type": "url",
+        "url": "https://pecl.php.net/get/yac",
+        "path": "php-src/ext/yac",
+        "filename": "yac.tgz",
+        "license": {
+            "type": "file",
+            "path": "LICENSE"
+        }
+    },
     "yaml": {
         "type": "git",
         "path": "php-src/ext/yaml",