compile: make the parse a function instead of inline

Again, prep for delegation, when we'll be reading fragments of config rules
from various files and tacking them onto the %repos hash.

note: this patch best viewed with "git diff -w", clicking "Ignore space
change" in gitk, or eqvt :-)

src/gl-compile-conf

@@ -119,7 +119,10 @@ sub expand_list
 #       "compile" GL conf
 # ----------------------------------------------------------------------------
 
-my $conf_fh = wrap_open( "<", $GL_CONF );
+sub parse_conf_file
+{
+    my ($conffile) = @_;
+    my $conf_fh = wrap_open( "<", $conffile );
 
     # the syntax is fairly simple, so we parse it inline
 
@@ -192,6 +195,9 @@ while (<$conf_fh>)
             die "$ATTN can't make head or tail of '$_'\n";
         }
     }
+}
+
+parse_conf_file($GL_CONF);
 
 my $compiled_fh = wrap_open( ">", $GL_CONF_COMPILED );
 print $compiled_fh Data::Dumper->Dump([\%repos], [qw(*repos)]);