Erlang webtool won't start

Just wondering what is going on with my Erlang webtool. I am running Ubuntu 15.10 and I have checked that the erlang-webtool package is installed. However, when I try to run it I get the following:

    1> webtool:start().
    {error,
        {shutdown,
            {failed_to_start_child,
                {httpd_instance_sup,{127,0,0,1},8888,default},
                {shutdown,
                    {failed_to_start_child,
                        {httpd_manager,{127,0,0,1},8888,default},
                        {error,
                            {invalid_option,
                                {module_does_not_exist,mod_include}}}}}}}}

    =ERROR REPORT==== 7-Mar-2016::15:47:36 ===
    Failed initiating web server: 
    undefined
    {invalid_option,{module_does_not_exist,mod_include}}

My version of Erlang: Erlang/OTP 18 [erts-7.0] [source] [64-bit] [smp:8:8] [async-threads:10] [kernel-poll:false]

Any ideas? Thanks.