[fix] add missing files required for compilation

Missing instructions in autogen.sh and missing jemalloc file to allow a
clean repo to compile.

autogen.sh

 #!/bin/sh
 set -ex
+
+# jemalloc
+(cd jemalloc; ./autogen.sh)
+
+# aml
 mkdir -p build-aux
 aclocal -I m4
+autoheader
 libtoolize
 automake --add-missing --copy
 autoconf