Tweak the bin/brew command selector a bit.
Tweak the bin/brew command selector a bit.

* Move 'brew doctor' above both unknown command blocks and then...
* Merge unknown command blocks.

(This is cleanup for supporting external brew commands.)

konqui/brew,mahori/brew,palxex/brew,zmwangx/brew,DomT4/brew,pseudocody/brew,jmsundar/brew,toonetown/homebrew,jmsundar/brew,muellermartin/dist,gordonmcshane/homebrew,claui/brew,MikeMcQuaid/brew,staticfloat/brew,ilovezfs/brew,nandub/brew,gregory-nisbet/brew,rwhogg/brew,zmwangx/brew,amar-laksh/brew_sudo,mistydemeo/homebrew,sjackman/homebrew,vitorgalvao/brew,MikeMcQuaid/brew,AnastasiaSulyagina/brew,ilovezfs/brew,amar-laksh/brew_sudo,alyssais/brew,Homebrew/brew,mahori/brew,sjackman/homebrew,AnastasiaSulyagina/brew,sjackman/homebrew,gordonmcshane/homebrew,palxex/brew,staticfloat/brew,nandub/brew,gregory-nisbet/brew,tonyg/homebrew,jmsundar/brew,DomT4/brew,reelsense/brew,bfontaine/brew,konqui/brew,zmwangx/brew,pseudocody/brew,EricFromCanada/brew,nandub/brew,reitermarkus/brew,Homebrew/brew,vitorgalvao/brew,mgrimes/brew,pseudocody/brew,ilovezfs/brew,JCount/brew,maxim-belkin/brew,hanxue/linuxbrew,palxex/brew,EricFromCanada/brew,JCount/brew,konqui/brew,reelsense/brew,aw1621107/brew,JCount/brew,toonetown/homebrew,claui/brew,hanxue/linuxbrew,AnastasiaSulyagina/brew,DomT4/brew,Linuxbrew/brew,muellermartin/dist,sjackman/homebrew,mahori/brew,mahori/brew,hanxue/linuxbrew,Linuxbrew/brew,Homebrew/brew,alyssais/brew,alyssais/brew,rwhogg/brew,gregory-nisbet/brew,bfontaine/brew,reitermarkus/brew,claui/brew,maxim-belkin/brew,bfontaine/brew,MikeMcQuaid/brew,EricFromCanada/brew,vitorgalvao/brew,JCount/brew,Linuxbrew/brew,MikeMcQuaid/brew,reitermarkus/brew,mgrimes/brew,gordonmcshane/homebrew,mistydemeo/homebrew,reitermarkus/brew,claui/brew,tonyg/homebrew,aw1621107/brew,Homebrew/brew,maxim-belkin/brew,mgrimes/brew,mistydemeo/homebrew,EricFromCanada/brew,tonyg/homebrew,konqui/brew,amar-laksh/brew_sudo,Linuxbrew/brew,rwhogg/brew,aw1621107/brew,staticfloat/brew,nandub/brew,DomT4/brew,reelsense/brew,toonetown/homebrew,vitorgalvao/brew,muellermartin/dist