Draft: Anti-Id Tau decoration and update of overlap removal

Also see #189 (closed)

• decorate all taus satisfying the anti-ID requirement with the corresponding flag
• [-] anti-tau objects would go through the first part of the overlap removal (all overlaps are removed except between anti-taus and non-b-jets), done in atlas/athena!69115 (merged)
• determine correct number of anti-taus (based on trigger matching and random selection where we don't trigger on taus), select in atlas/athena!69115 (merged)
• run second part of the overlap removal, between anti-taus and light jets should be performed in favor of anti-taus, done in atlas/athena!69115 (merged)

Tagging @pbokan