Add vmod_parseform

Remove vmod_parsereq. Because this vmod is retired.

R1/source/vmods/vmod_parseform.json

+{
+    "date": "2017-08-22",
+    "desc": "Parse POST field",
+    "github": {
+        "branches": {
+            "5.1": "varnish51",
+            "master": "master"
+        },
+        "project": "libvmod-parseform",
+        "user": "xcir",
+        "vcc_path": "src/vmod_parseform.vcc",
+        "doc_path": "README.rst"
+    },
+    "license": "FreeBSD",
+    "name": "parseform",
+    "status": "development",
+    "maintainer": "kokoniimasu@gmail.com"
+}

R1/source/vmods/vmod_parsereq.json

-{
-    "date": "YYYY-MM-DD",
-    "desc": "POST/GET/Cookie parse",
-    "github": {
-        "branches": {
-            "3.0": "master"
-        },
-        "project": "libvmod-parsereq",
-        "user": "xcir",
-        "vcc_path": "src/vmod_parsereq.vcc"
-    },
-    "license": "FreeBSD",
-    "name": "parsereq",
-    "status": "development"
-}
\ No newline at end of file