Merge branch '44-allow-graph-vizualization-also-to-be-left-right-and-not-only-top-bottom' into 'main'

Resolve "allow graph vizualization also to be Left-> Right and not only Top->Bottom"

Closes #44

See merge request !10

added to_dot_test

Resolve "Write text for THRILL page"

Closes #38

See merge request !9

Resolve "Beam splitter: Check splitting ratio"

Closes #40

See merge request !6

Add unit tests.

Resolve "Implement "inverted" feature for group nodes"

Closes #14

See merge request !5

The original graph is kept untouched.

Update names of components in filter_test