Test glexec at startup, if configured to use it - merge from branch_v2_5_1plus_ucsd1
Test glexec at startup, if configured to use it - merge from branch_v2_5_1plus_ucsd1

holzman/glideinwms-old,holzman/glideinwms-old,bbockelm/glideinWMS,bbockelm/glideinWMS,holzman/glideinwms-old,bbockelm/glideinWMS,bbockelm/glideinWMS