GitLab

* Auto generate mapping files with command `java -jar grasscutter.jar -gachamap`

* Static file provider
  * For gacha record webpage
  * All static files should be stored at `GRASSCUTTER_RESOURCE/gcstatic/`
  * Can benefit other subsystem in future when webpages involved

* Frontend is not very beautiful yet
* Didn't include too much `some anime game` data in the page to avoid being DMCA'd