Merge pull request #496 from telefonicaid/bug/493

ReplicaSet support
each send is considered an transaction
fixes during PR review
Fixes
Merge pull request #502 from telefonicaid/hardening/sonar_memory_fixes

Sonar detected memory fixes
Merge branch 'release/iotplatform-v1' into hardening/sonar_memory_fixes
Merge pull request #504 from telefonicaid/hardening/sonar_memory_fixes

Sonar detected memory fixes (into release/iotplatfor-v1)
ADD reference info also for sucessfull notifications
FIX notification sucessfully sent including URL in the "hidden" function also
FIX in previous commit
Merge pull request #498 from telefonicaid/bug/478_transactions

each send is considered a transaction
Merge pull request #508 from telefonicaid/bug/478_transactions

each send is considered a transaction (into develop)
FIX documentation
Merge branch 'develop' into hardening/doc_improvement
Merge pull request #510 from telefonicaid/hardening/doc_improvement

 Improve README.md (into develop)