Add newlines after headings for best practice, trim trailing spaces & convert sneaky incorrectly coded chars

blank newline after headins is apparently best practice according to http://stackoverflow.com/q/42953462/1292918

Add GFM version of getting started guide PDF

Add GFM version of configuration guide PDF

Add GFM version of helper scripts guide PDF

Add GFM version of coding standard PDF

Add GFM version of assertions reference PDF

Change markdown used to italicise line. Switched to use asterisk markdown instead