Add linetrace=True in DefaultPassGroup

[yuqisun]

test_harness.apply(DefaultPassGroup(linetrace = True)) can enable the simulator to automatically call the line_trace method.

[yuqisun]

Also find an interesting method test_harness.print_textwave() which can print each value by clk, such as below:
Would it be helpful in verbose trace? (looks cool)

[tancheng]

Also find an interesting method test_harness.print_textwave() which can print each value by clk, such as below: Would it be helpful in verbose trace? (looks cool)

Looks good, you can have a wave mode or sth like that.