Add back technical debt estimations for issues

[rcastagno]

Issue #10 implemented squale.xml with values for remediationFunction, used to evaluate the technical debt and ultimately the maintainability score.

I see that this have been removed with this commit Update to Sonar 6.5 and add logs 45c04c06eac501d421efbd2d890b8a1ea8fcbd2a

Is it possible to add it back?

Without this technical debt no longer influences the maintainability score, and consequently never fails the quality gate.