Add parameter file generation reference to the initial BCI run description

[glemieux]

We should add a parameter file modification/generation cross reference from docs/source/parameter_file_tools.md to the create scripts section:

fates-tutorial/docs/source/create_scripts.md

Lines 159 to 168 in 702666f

	The next bit is where we edit the user_nl_elm file. The user_nl_elm file specifies
	namelist options, such as which optional modules to turn on, and points to the parameter file and inventory data.
	It also defines which history variables to output.
	```
	# point to your parameter file
	# add any history variables you want
	cat >> user_nl_elm <<EOF
	fsurdat = '${ELM_SURFDAT_DIR}/${ELM_USRDAT_SURDAT}'
	fates_paramfile='${PARAM_FILES}/fates_params_default-1pft.nc'

This came up per #62