Allow specifying destination when building item

src/include/build.sh

@@ -21,7 +21,8 @@ build1() {
     #
     local srcpath dstpath
     srcpath=$1
-    dstpath=${srcpath%.skel}
+    dstpath=$2
+    test -n "$dstpath" || dstpath=${srcpath%.skel}
     case $dstpath in
         *.md) <"$srcpath" expand_includes | expand_variables >"$dstpath" ;;
         *)    <"$srcpath"                   expand_variables >"$dstpath" ;;