Set default bin paths to /usr/bin

Admins should configure (manually or via osg-configure) this to a path
and we shouldn't support shell evaluation in config:

1. Avoid $PATH tomfoolery
2. Why add the overhead of `which`?

config/blah.config.template

@@ -80,7 +80,7 @@ blah_require_proxy_on_submit=
 
 #Path where PBS executables are located 
 # NOTE: this path is computed many times; I worry about the overhead here.  -BB, 12-13-2012
-pbs_binpath=`which qsub 2>/dev/null|sed 's|/[^/]*$||'`
+pbs_binpath=/usr/bin
 
 #Path where the PBS logs are located ($pbs_spoolpath/server_logs)
 #pbs_spoolpath=
@@ -105,7 +105,7 @@ pbs_pro=no
 ##LSF common variables
 
 #Path where LSF executables are located 
-lsf_binpath=`which bsub 2>/dev/null|sed 's|/[^/]*$||'`
+lsf_binpath=/usr/bin
 
 #Path where the LSF conf file is located ($lsf_confpath/lsf.conf)
 lsf_confpath=
@@ -285,7 +285,7 @@ tracejob_max_output=
 ##Condor
 
 #condor bin location
-condor_binpath=`which condor_submit 2>/dev/null|sed 's|/[^/]*$||'`
+condor_binpath=/usr/bin
 
 #path to condor_config
 #export CONDOR_CONFIG="/etc/condor/condor_config"