zsh: Depends on texinfo for Linuxbrew
zsh: Depends on texinfo for Linuxbrew

Fix error:
/bin/sh: line 3: makeinfo: command not found
make[1]: *** [install.info] Error 1
make[1]: Leaving directory `/tmp/zsh20150713-13485-19a2t7g/zsh-5.0.8/Doc'
make: *** [install.info] Error 2

Closes #477.

Signed-off-by: Shaun Jackman <b580dab3251a9622aba3803114310c23fdb42900@gmail.com>

gnubila-france/linuxbrew,IsmailM/linuxbrew,Homebrew/linuxbrew,romejoe/linuxbrew,gcstang/linuxbrew,jwillemsen/linuxbrew,princeofdarkness76/linuxbrew,Angeldude/linuxbrew,brevilo/linuxbrew,DoomHammer/linuxbrew,drbenmorgan/linuxbrew,gnubila-france/linuxbrew,davydden/linuxbrew,saketkc/linuxbrew,amenk/linuxbrew,ebouaziz/linuxbrew,davydden/linuxbrew,lvicentesanchez/linuxbrew,brevilo/linuxbrew,hyokosdeveloper/linuxbrew,sjackman/linuxbrew,Linuxbrew/linuxbrew,caputomarcos/linuxbrew,SuperNEMO-DBD/cadfaelbrew,jack-and-rozz/linuxbrew,saketkc/linuxbrew,dholm/linuxbrew,ebouaziz/linuxbrew,bukzor/linuxbrew,princeofdarkness76/linuxbrew,tjhei/linuxbrew,adamliter/linuxbrew,saketkc/linuxbrew,bukzor/linuxbrew,adamliter/linuxbrew,reelsense/linuxbrew,caputomarcos/linuxbrew,DoomHammer/linuxbrew,Linuxbrew/linuxbrew,sjackman/linuxbrew,ebouaziz/linuxbrew,arcivanov/linuxbrew,gnubila-france/linuxbrew,lvicentesanchez/linuxbrew,jack-and-rozz/linuxbrew,SuperNEMO-DBD/cadfaelbrew,jbaum98/linuxbrew,DoomHammer/linuxbrew,saketkc/linuxbrew,princeofdarkness76/linuxbrew,IsmailM/linuxbrew,gnubila-france/linuxbrew,drbenmorgan/linuxbrew,lvicentesanchez/linuxbrew,amenk/linuxbrew,Linuxbrew/linuxbrew,sjackman/linuxbrew,danabrand/linuxbrew,caputomarcos/linuxbrew,romejoe/linuxbrew,lvicentesanchez/linuxbrew,amenk/linuxbrew,tomas/linuxbrew,hyokosdeveloper/linuxbrew,arcivanov/linuxbrew,sjackman/linuxbrew,adamliter/linuxbrew,jwillemsen/linuxbrew,jwillemsen/linuxbrew,gcstang/linuxbrew,tjhei/linuxbrew,hyokosdeveloper/linuxbrew,drbenmorgan/linuxbrew,bukzor/linuxbrew,adamliter/linuxbrew,danabrand/linuxbrew,LeonB/linuxbrew,drbenmorgan/linuxbrew,bukzor/linuxbrew,IsmailM/linuxbrew,Homebrew/linuxbrew,outcoldman/linuxbrew,danabrand/linuxbrew,brevilo/linuxbrew,jack-and-rozz/linuxbrew,LeonB/linuxbrew,danabrand/linuxbrew,arcivanov/linuxbrew,outcoldman/linuxbrew,jbaum98/linuxbrew,outcoldman/linuxbrew,DoomHammer/linuxbrew,reelsense/linuxbrew,amenk/linuxbrew,tjhei/linuxbrew,reelsense/linuxbrew,davydden/linuxbrew,tomas/linuxbrew,jbaum98/linuxbrew,Angeldude/linuxbrew,IsmailM/linuxbrew,Angeldude/linuxbrew,dholm/linuxbrew,ebouaziz/linuxbrew,romejoe/linuxbrew,davydden/linuxbrew,Homebrew/linuxbrew,LeonB/linuxbrew,reelsense/linuxbrew,gcstang/linuxbrew,Angeldude/linuxbrew,hyokosdeveloper/linuxbrew,Homebrew/linuxbrew,dholm/linuxbrew,tomas/linuxbrew,SuperNEMO-DBD/cadfaelbrew,Linuxbrew/linuxbrew,SuperNEMO-DBD/cadfaelbrew,jbaum98/linuxbrew,tomas/linuxbrew,caputomarcos/linuxbrew