Defer registry state cleanup (elastic#6347) (elastic#6812)

- Defer registrar state gc until the registry needs to be written.
- when updating regitrar states from batch, ensure all updated states will
have same timestamp.

Depends on elastic#6346

(cherry picked from commit 2d2400b)

Fix minor panic in http parser (elastic#6750)

There was a bounds check error in parsing HTTP responses. A malformed
response line in the form "HTTP/1.1\r\n" would cause a panic when parsed.

Related to elastic#6409

Remove unused packer deb6 files (elastic#6532)

Remove unused packer deb6 files (elastic#6533)

Fix typo in docs (elastic#6386)

5.6: Fix event formatting with missing params (elastic#6352)

* Winlogbeat: Fix event formatting with missing params

There was a crash in the eventlogging module used in legacy Windows
versions (XP and 2003 server). It is necessary to account for the case
where an event contains fewer parameters than required by its format
string.

Closes elastic#6234

fix packetbeat devices command (elastic#6307) (elastic#6311)

The -devices flag is not valid, it yields:

/usr/share/packetbeat/bin/packetbeat -devices
Error: unknown flag: --devices

The command is "packetbeat devices"

(cherry picked from commit b8ded9b)

Add monitoring settings to reference configuration (elastic#6254) (el…

…astic#6259)

* Add monitoring settings to reference configuration

Note that monitoring is disabled by default in Beats.

* Addressed comments

(cherry picked from commit 26cd205)

Close changelog for the 6.1.3 release (elastic#6163)

Also updated the testing env. Can be merged right away.

Bump version to 5.6.7 in the 5.6 branch (elastic#6095)

In preparation for the next release.