[node] Enable npm to build mapbox-gl-native package from source

- Allow node bindings to be built if git submodules cannot be checked out
 - Made geojsonvt a mason package instead of a git submodule
 - Use globally installed mason if it cannot be checked out via git submodules

scripts/linux/configure.sh

@@ -11,6 +11,8 @@ LIBUV_VERSION=0.10.28
 ZLIB_VERSION=system
 NUNICODE_VERSION=1.5.1
 LIBZIP_VERSION=0.11.2
+GEOJSONVT_VERSION=1.1.0
+VARIANT_VERSION=1.0
 
 function print_opengl_flags {
     CONFIG+="    'opengl_cflags%': $(quote_flags $(pkg-config gl x11 --cflags)),"$LN