Removed thread limit, by replacing FixedThreadPool with

CachedThreadPool.
Also removed all google analitics.

add note about plugins

add another note

add release notes

bump version and add release notes

remove word draft

add 3.5.5 release notes

make Brazilian Portuguese translation actually work

bugfix: track number of users of a shared pinger and close it only af…

…ter nobody needs it anymore

update MAC vendors