Implement Trace annotations converter

[d0rich]

Annotations in .Trace.csv are different to be mapped to requirements, because they have small context. These annotations are in fact logs of the model and since they are grouped by test cases we can create one big annotation for each test case.

Create convert_trace_annos utility taking path to .Trace.csv file and writing expected annotations to a csv file or to SQLite database.

Annotations before:

#testcase	Annotation
tc1	step1
tc1	step2
tc1	step3
tc2	step4
tc2	step5

Annotations after:

#testcase	Annotation
tc1	step1, step2, step3
tc2	step4, step5