Generate shared object

Modify build-script to generate a shared library for Godot.

configure.ac

@@ -7,6 +7,8 @@ AC_INIT(\
         [https://www.delay.cloud/] \
         )
 
+AC_COPYRIGHT(ISC License)
+
 # AC_CHECK_LIB is not utilized, since it checks the presence of libraries by
 # linking them to test program; this process introduces more overhead and longer
 # build times.
@@ -19,6 +21,12 @@ AM_CONFIG_HEADER([src/config.h])
 AC_CONFIG_MACRO_DIR([m4
                     ])
 
+AC_PROG_LIBTOOL
+AC_PROG_INSTALL
+
+AC_ENABLE_SHARED
+AC_DISABLE_STATIC
+
 # Do not generate GNU project files and disable some checks.
 # Includes flags to strictly compile Standard C89.
 AM_INIT_AUTOMAKE([\