back-port start_with? from 1.8.7
back-port start_with? from 1.8.7

This allows its use in Leopard, which has Ruby 1.8.6.

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