Documentation: add autoconf to build time requirements
Documentation: add autoconf to build time requirements

Required by autogen.

monstermunchkin/rkt,endocode/rkt,Shashwatsh/rkt,tmrts/rkt,blixtra/rkt,jjlakis/rkt,yifan-gu/rkt,kbrwn/rkt,lucasallan/rkt,s-urbaniak/rkt,yifan-gu/rocket,Wilybald/rkt,matthaias/rkt,squeed/rkt,akshaykarle/rkt,squeed/rkt,krnowak/rkt,kinvolk/rkt,blixtra/rkt,joshix/rkt,sstabellini/rkt,kinvolk/rkt,jasonchaffee/rkt,jzelinskie/rkt,monstermunchkin/rkt,sstabellini/rkt,jasonchaffee/rkt,kbrwn/rkt,coreos/rkt,krnowak/rkt,adfernandes/rkt,rkt/rkt,endocode/rkt,il9ue/rkt,dgonyeo/rkt,nhlfr/rkt,adfernandes/rkt,monstermunchkin/rkt,jonboulle/rkt,achanda/rkt,markllama/rkt,akshaykarle/rkt,alban/rkt,sgotti/rkt,lucasallan/rkt,sstabellini/rkt,tmrts/rkt,liugenping/rkt,kbrwn/rkt,intelsdi-x/rkt,jakon89/rkt,matthaias/rkt,alban/rkt,lucasallan/rkt,linki/rkt,yifan-gu/rocket,sinfomicien/rkt,kinvolk/rkt,jzelinskie/rkt,joshix/rkt,achanda/rkt,jonboulle/rkt,cab105/rkt,sinfomicien/rkt,Shashwatsh/rkt,yifan-gu/rkt,shobhit85/rkt,liugenping/rkt,mike1729/rkt,linki/rkt,il9ue/rkt,cab105/rkt,mike1729/rkt,Wilybald/rkt,alban/rkt,euank/rkt,euank/rkt,lucasallan/rkt,Shashwatsh/rkt,matthaias/rkt,s-urbaniak/rkt,mike1729/rkt,dgonyeo/rkt,ybubnov/rkt,coreos/rkt,jzelinskie/rkt,il9ue/rkt,joshix/rkt,tmrts/rkt,joshix/rkt,sinfomicien/rkt,cab105/rkt,markllama/rkt,rkt/rkt,nhlfr/rkt,rkt/rkt,yifan-gu/rocket,akshaykarle/rkt,shobhit85/rkt,jakon89/rkt,iaguis/rkt,coreos/rkt,shobhit85/rkt,liugenping/rkt,ybubnov/rkt,endocode/rkt,iaguis/rkt,markllama/rkt,euank/rkt,ybubnov/rkt,yifan-gu/rkt,jakon89/rkt,jasonchaffee/rkt,s-urbaniak/rkt,squeed/rkt,Wilybald/rkt,sgotti/rkt,jonboulle/rkt,intelsdi-x/rkt,kinvolk/rkt,blixtra/rkt,intelsdi-x/rkt,adfernandes/rkt,jjlakis/rkt,achanda/rkt,dgonyeo/rkt,jjlakis/rkt,nhlfr/rkt,Wilybald/rkt,rkt/rkt,krnowak/rkt,iaguis/rkt,sgotti/rkt,linki/rkt