Update links in Developer Community section

[dmitryvinn]

In the Developer Community section of the guide, there are a few items which might need some adjustment:

1. Event List seems to be deprecated, so we can probably remove it from the list
2. Company Blog does not exist on Medium anymore. Is there a new one out there, or should we completely remove this item from the list (or merge with the engineering blog)?

Additionally, we probably should update a maintainer to myself or Victor.