Add new tests to backends and architecture;
Merge commit "Add regression test for Yosys PR 896"

5. clk2fflogic (104 - 144,180-195 are not covered)
9. memory_nordff(75-101 is not covered)
10. memory_unpack(91-108 is not covered)
12. hierarchy (the coverage from 44% increased to 61,3%)