Correct install problems under Cygwin

- configure.pl doesn't understand CYGWIN return from uname
- shorewall-core install.sh doesn't understand CYGWIN return from uname
- shorewall install.sh generates 'mkdir -p //etc/shorewall' which is
  broken under Cygwin

Signed-off-by: Tom Eastep <teastep@shorewall.net>

Shorewall-core/configure.pl

@@ -100,7 +100,7 @@ if ( defined $vendor ) {
     } elsif ( `uname` =~ '^Darwin' ) {
 	$vendor = 'apple';
 	$rcfilename = 'shorewallrc.apple';
-    } elsif ( `uname` =~ '^Cygwin' ) {
+    } elsif ( `uname` =~ /^Cygwin/i ) {
 	$vendor = 'cygwin';
 	$rcfilename = 'shorewallrc.cygwin';
     } else {

Shorewall-core/install.sh

@@ -187,7 +187,7 @@ INSTALLD='-D'
 
 if [ -z "$BUILD" ]; then
     case $(uname) in
-	cygwin*)
+	cygwin*|CYGWIN*)
 	    BUILD=cygwin
 	    ;;
 	Darwin)

Shorewall/install.sh

@@ -399,7 +399,7 @@ fi
 #
 # Create /etc/$PRODUCT and other directories
 #
-mkdir -p ${DESTDIR}/${CONFDIR}/$PRODUCT
+mkdir -p ${DESTDIR}${CONFDIR}/$PRODUCT
 mkdir -p ${DESTDIR}${LIBEXECDIR}/$PRODUCT
 mkdir -p ${DESTDIR}${PERLLIBDIR}/Shorewall
 mkdir -p ${DESTDIR}${SHAREDIR}/$PRODUCT/configfiles