Bug 131521 - Set $::ENV{PATH} so that we don't get bogus 15 line warnings

from perl 5.6.1's Cwd.pm on every system() call.
r=mattyt, justdave

webtools/bugzilla/globals.pl

@@ -86,6 +86,11 @@ use File::Spec;
 # Some environment variables are not taint safe
 delete @::ENV{'PATH', 'IFS', 'CDPATH', 'ENV', 'BASH_ENV'};
 
+# Cwd.pm in perl 5.6.1 gives a warning if $::ENV{'PATH'} isn't defined
+# Set this to '' so that we don't get warnings cluttering the logs on every
+# system call
+$::ENV{'PATH'} = '';
+
 # Contains the version string for the current running Bugzilla.
 $::param{'version'} = '2.15';