Added g_sim_flash_model to ensure only one instance of flash model, to avoid double driver failure in sim.

Renamed key hdl_lib_uses into hdl_lib_uses_synth and added new key hdl_lib_uses_sim for extra test_bench_files library dependencies.

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.

Used hdl_config.py with mode=1 to change build_synth_dir key value into /home/kooistra/svnroot/UniBoard_FP7/RadioHDL/trunk/build for all hdllib.cfg dictionary files.