try to improve compile time a bit by gating all the bindings behind features too
// our actual bindings modules -- these are generated by build.rs
//
+#[cfg(feature = "pg10")]
mod pg10_bindings;
+
+#[cfg(feature = "pg11")]
mod pg11_bindings;
+
+#[cfg(feature = "pg12")]
mod pg12_bindings;
//
