Bump version in 'configure' as well

configure.ac

@@ -23,7 +23,7 @@
 #
 AC_PREREQ([2.64])
 LT_PREREQ([2.4.0])
-AC_INIT([GNU libmicrohttpd],[0.9.76],[[email protected]])
+AC_INIT([GNU libmicrohttpd],[0.9.77],[[email protected]])
 AC_CONFIG_AUX_DIR([build-aux])
 MHD_AUX_DIR='build-aux' # Must be set to the same value as in the previous line
 AC_CONFIG_HEADERS([MHD_config.h])