added source to composer.json as recommend by @rarst in #50
added source to composer.json as recommend by @rarst in #50

mojaray2k/timber,Jmayhak/timber,gchtr/timber,PrisisForks/timber,ogrosko/timber,aaemnnosttv/timber,mgmartel/timber,joelgarciajr84/timber,aprendiendoando/timber,jnweaver/timber,rpkoller/timber,joelgarciajr84/timber,gbarberi/timber,josephbergdoll/timber,josephbergdoll/timber,rpkoller/timber,timber/timber,anugupta/timber,gbarberi/timber,PrisisForks/timber,anugupta/timber,blocher/timber,xavivars/timber,josephbergdoll/timber,mojaray2k/timber,xavierpriour/timber,gchtr/timber,ogrosko/timber,Jmayhak/timber,lucasmichot/timber,xavivars/timber,pensesmart/timber,jarednova/timber,jnweaver/timber,lucasmichot/timber,blocher/timber,jarednova/timber,joelgarciajr84/timber,Jmayhak/timber,xavierpriour/timber,timber/timber,aprendiendoando/timber,blocher/timber,gbarberi/timber,aaemnnosttv/timber,rpkoller/timber,gchtr/timber,PrisisForks/timber,anugupta/timber,xavivars/timber,jnweaver/timber,pensesmart/timber,mgmartel/timber,pensesmart/timber,aaemnnosttv/timber,ogrosko/timber,lucasmichot/timber,aprendiendoando/timber,mojaray2k/timber,mgmartel/timber,jarednova/timber,xavierpriour/timber