Verify CLK trees

[ogamespec]

We need to verify that CLK trees are correctly represented and their polarity is treated correctly in all project materials.

[ogamespec]

Overall looks like no problems, except for this one:

// Regular posedge DFF (dual rails)
module seq_dff_posedge_comp ( d, clk, cclk, q );

	input d;	
	input clk;
	input cclk;
	output q;

	reg val;
	initial val = 1'bx;

	// XXX: Initially, clk and cclk were mixed up when parsing the netlist. So read here cclk as clk. Not a very nice mix-up, but this is always the case with clk.
	always @(posedge cclk) begin
		val <= d;
	end

	assign q = val;

endmodule // seq_dff_posedge_comp