Retrieve account-characters per GW2 API and save them to database

[AniOnGit]

• Do DB changes if necessary
• Implement link on profile page
• implement the sync

There shouldn't be - at least in this version - a auto sync, but only when the user clicks on the link on his profile page,

[wwevo]

I would store these things in the personal settings table for now. Until we need some serious handling of this data, a serialized data-package in let's say settings->account_characters should suffice. This should be revisited when we implement functions that handle characters inventories and suchlike.

[wwevo]

Implemented a basic import. Nothing automatic as of yet, one mouse-click is required. For now there's a table in the API page, for now I'd like to collect and test functions that use the API there

[wwevo]

this is easily accessible from the profile page now