Fixed defect ZEN-13190
Fix for ZEN-13549
Fix for ZEN-13588
Fix for ZEN-13662
Fix for ZEN-13662: fixed property id
release: version 2.1.0 -> 2.1.2
post release: 2.1.2 -> 2.1.3dev
Documentation update

Added sections regarding using WinCOmmand notification and
modeling/monitoring MSSQL Server instances.
Document ZEN-13662
Document ZEN-13662: typo
Document ZEN-13662: added info about MSSQL
Edit and update grammer in README
update release note changes for 2.1.2