Renamed build_sim_dir into build_dir_sim, similar build_dir_synth. Use...

Renamed build_sim_dir into build_dir_sim, similar build_dir_synth. Use <tool_name>_copy_key based on build type 'sim' or 'synth' from hdltool.cfg. Renamed sim_tool_name into tool_name_sim in hdltool.cfg, similar for synth_tool_name.