Benchmarking histogram

Description

Able to create histograms from benchmarking data. Uses a FreeMarker template and Chartjs to generate a HTML file report. Closes #162 (closed)

Changes

Changed way benchmarker calculates weight: uses fallback metrics + sum of children weight instead of only checking for LINES_OF_CODE metric.

Additions

• Added freemarker template for report
• Added page to old UI to display chart
• Added new endpoints to controller

Test and Review

To be filled in by the reviewers

• All of the methods are commented to expectation

• The methods are tested to satisfaction

• There are no unnecessary files present in the MR

• The continuous integration has no problems with the MR

• The MR is filled in as requested (including labels, milestones, and reviewers)

• The documentation is up-to-date

• All nullable parameters are marked as such

changed milestone to %Benchmarking

added typefeature-request + 1 deleted label

changed the description

Could you also add an image of an example of a histogram and an image of the jacoco report of the relevant classes.