Remove unused dependencies.

Removed 'psutil' and 'memory-profiler' from the requirements.txt file.
Those dependencies where added only to profile the receiver performance,
now they are not required anymore.
Close #72
Merge branch 'enhancement-#72' into develop
Update .travis.yml

The lastest changes to the model have been merged into its main branch.
The .travis.yml file does not need to checkout in the model repo anymore.
Close #73

SQL-Service was updated to reflect the lastest changes in the model
and in the XML Schema.
Merge branch 'enhancement-#73' into develop
Close #75
Merge branch 'enhancement-#75' into develop
Close #74
Merge branch 'enhancement-#74' into develop
Add file check in incoming request
Fix merge conflicts
Add file check in request