Update links to new repositories

After a long discussion, it turned out that CodiMD as community project
and HackMD as a company, have fundamental different views on the project
governance.

Due to this, it came to point where the decision for a fork was made.
After the fork and move towards an own organisation, this patch updates
all links inside the project to the new repositories.

Signed-off-by: Sheogorath <sheogorath@shivering-isles.com>

package.json

@@ -140,7 +140,7 @@
   "engines": {
     "node": ">=6.x"
   },
-  "bugs": "https://github.com/hackmdio/codimd/issues",
+  "bugs": "https://github.com/codimd/server/issues",
   "keywords": [
     "Collaborative",
     "Markdown",
@@ -159,7 +159,7 @@
   ],
   "repository": {
     "type": "git",
-    "url": "https://github.com/hackmdio/codimd.git"
+    "url": "https://github.com/codimd/server.git"
   },
   "devDependencies": {
     "babel-cli": "^6.26.0",