Support folding for VHDL 08 else-generate and case-generate

[danselmi]

Folding of if cond generate ... elsif cond generate ... else generate ... end generate; and case sel generate ... end generate; was not working.
These two are new with vhdl 08.

[nyamatongwe]

This needs a working test case in test/examples/vhdl that exercises the change. Read about creating and running tests in test/README.

Unfortunately, the VHDL lexer currently assigns different styles to Windows-style (\r\n) line end bytes after comments which upsets the test runner. Either avoid comments in the test case or change the comment ending behaviour to be like LexPython (sc.ch == '\r' || sc.ch == '\n') or LexCPP (sc.atLineStart).

[nyamatongwe]

Searched for an example that includes generate (http://esd.cs.ucr.edu/labs/tutorial/FIR.vhd) and the patch stops folding on generate. The code is (truncated):

    gen8:	for j in K-1 downto 0 generate
	
        stages:	process (rst, clk)
        begin
		-- ...
        end process;
		
    end generate;

[danselmi]

fixed it.
also added a test case.
thanks

[nyamatongwe]

Committed most recent changes with some more additions as ff879c5. The main addition was to rerun TestLexers which updated the .styled and .folded files as there were a couple of missing sections -- in 0e497af, the .vhd is 57 lines long but the generated files are 47/46 lines long. Also added a change log entry. Please check the current repository state.

[nyamatongwe]

Included in 5.1.7 release.