Register Stream connectors early on priority 0 of init hook

[shadyvb]

Fixes #501 , but would probably need some good testing to make sure everything else works, specially extensions, as this might make it difficult to hook/modify some behavior of
connectors.

/cc @fjarrett @lukecarbis

[frankiejarrett]

@shadyvb This does not appear to be working for me.

The only records that appear are for Logout and there are no records for Login.

[shadyvb]

@fjarrett Works after merging develop with the custom authentication tracking fix.

[frankiejarrett]

I've tested this again and it's working great. Notifications are also still working fine and the Reports also look good too.

/cc @lukecarbis @Japh please do some sanity checks on this one for me.

[lukecarbis]

I've tested and everything works for me. I focused particularly on Extensions (connecting, installing, activating, etc.) and Exporter.