Accept style_convert parameter to GET /styl request

Require grainstore-0.10 and windshaft-0.8 to allow for it

npm-shrinkwrap.json

@@ -182,11 +182,8 @@
       "version": "1.3.3"
     },
     "grainstore": {
-      "version": "0.9.7",
+      "version": "0.10.0",
       "dependencies": {
-        "semver": {
-          "version": "1.1.0"
-        },
         "carto": {
           "version": "0.9.3-cdb1",
           "from": "git://github.com/CartoDB/carto.git#cdb-0.9",
@@ -251,7 +248,7 @@
       }
     },
     "windshaft": {
-      "version": "0.7.1",
+      "version": "0.8.0",
       "dependencies": {
         "express": {
           "version": "2.5.11",

package.json

@@ -21,8 +21,8 @@
         "cluster2": "git://github.com/CartoDB/cluster2.git#cdb_production",
         "node-varnish": "0.1.1",
         "underscore"  : "~1.3.3",
-        "grainstore"  : "~0.9.7",
-        "windshaft"  : "~0.7.0",
+        "grainstore"  : "~0.10.0",
+        "windshaft"  : "~0.8.0",
         "step": "0.0.x",
         "generic-pool": "1.0.x",
         "redis": "0.7.2",