Modify the C3D parameters in the TRIAL group.

This was implemented to import selected parameters from Vicon's .enf file that contains trial specific information.

Only the listed parameters are updated.

The user can also manually enter data into the parameters.

NOTES, DESCRIPTIONS, and SUBJECTS accept multiple entries.

Modify_C3D_Trial_Parameters /LOAD_ENF_FILE=TRUE /NOTES=Stumble before this trial /DESCRIPTIONS= /SUBJECTS=20120607_1530 /CREATION_DATE=2013_0718 /APPEND_TO_EXISTING_DATA=FALSE /OVERWRITE_C3D_FILE=FALSE ;