Function: IUG_LOAD_GMAG_WDC_VSNAMES function iug_load_gmag_wdc_vsnames Purpose: return valid site names for WDC data. Notes: This procedure is called from load procedures for WDC format data, 'iug_load_gmag_wdc*' provided by WDC Kyoto. WDC station list was provided at online data catalogue: http://wdc.kugi.kyoto-u.ac.jp/catmap/obs.html Todo: 1) Modify to read station-list file. 2) Modify to get station-list files from cgi or mdb via file_transfer. Written by: Daiki Yoshida, Sep 14, 2010