Update to svelte 2.6.4 (#322)

* fix(package): update svelte to version 2.6.4

Closes #172

* chore(package): update lockfile

https://npm.im/greenkeeper-lockfile

package-lock.json

@@ -10039,9 +10039,9 @@
       "integrity": "sha1-U10EXOa2Nj+kARcIRimZXp3zJMc="
     },
     "svelte": {
-      "version": "2.6.3",
-      "resolved": "https://registry.npmjs.org/svelte/-/svelte-2.6.3.tgz",
-      "integrity": "sha512-SHf8u74424sbpK/FQBeH1OeCGORrMN9nfx26BJ/opP4mTlS4MoyyZYM865fo3H4+lga57V7QuMGQrrISDO2qdQ=="
+      "version": "2.6.4",
+      "resolved": "https://registry.npmjs.org/svelte/-/svelte-2.6.4.tgz",
+      "integrity": "sha512-C4TqnvK9GfEePCWUzVvZTHEb07In+8wWDjKfwe8UotEHVZXiHYlPOeTSt93Qp9K8rzgPw91MOdt3jYxTmDTRuQ=="
     },
     "svelte-dev-helper": {
       "version": "1.1.7",

package.json

@@ -77,7 +77,7 @@
     "shrink-ray-current": "2.1.0",
     "stringz": "1.0.0",
     "style-loader": "0.21.0",
-    "svelte": "2.6.3",
+    "svelte": "2.6.4",
     "svelte-extras": "2.0.2",
     "svelte-loader": "2.9.1",
     "svelte-transitions": "1.2.0",