Add method to ENV for setting up a debug build
Add method to ENV for setting up a debug build

`ENV.Og` clears all optimization flags and adds `-g -O0`.

Signed-off-by: Adam Vandenberg <34c2b6407fd5a10249a15d699d40f9ed1782e98c@gmail.com>

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