uninstall: better message when dependents remain
uninstall: better message when dependents remain

Suggested by @MikeMcQuaid

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