Fix: nginx was always installed on ubuntu

sed match was expecting nginx to be at the beginning of the software list

install/hst-install-debian.sh

@@ -723,7 +723,7 @@ fi
 # Excluding packages
 software=$(echo "$software" | sed -e "s/apache2.2-common//")
 if [ "$nginx" = 'no'  ]; then
-    software=$(echo "$software" | sed -e "s/^nginx//")
+    software=$(echo "$software" | sed -e "s/\bnginx\b/ /")
 fi
 if [ "$apache" = 'no' ]; then
     software=$(echo "$software" | sed -e "s/apache2 //")

install/hst-install-ubuntu.sh

@@ -685,7 +685,7 @@ fi
 # Excluding packages
 software=$(echo "$software" | sed -e "s/apache2.2-common//")
 if [ "$nginx" = 'no'  ]; then
-    software=$(echo "$software" | sed -e "s/^nginx//")
+    software=$(echo "$software" | sed -e "s/\bnginx\b/ /")
 fi
 if [ "$apache" = 'no' ]; then
     software=$(echo "$software" | sed -e "s/apache2 //")