Update 'SSH' and 'Query' sections in Gerrit 2.6 release notes

Add descriptions of further SSH releated features and bug-fixes.

Have query related features and bug-fixes in an own section, since
queries can be executed in different ways, not only via SSH.

Some points are removed since they describe things that were already
included in 2.5.x.

Change-Id: If52cee15e14a79e3088a45c840b9213101d55879
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>
1 file changed