patch applied (ghc): Add a warning for tabs in source files

[Donald Bruce Stewart]

igloo:
> Fri Jan 12 08:47:32 PST 2007  Ian Lynagh <igloo at earth.li>
>   * Add a warning for tabs in source files
> 
>     M ./compiler/cmm/CmmParse.y -3 +7
>     M ./compiler/main/DynFlags.hs +2
>     M ./compiler/main/HeaderInfo.hs -4 +8
>     M ./compiler/main/HscMain.lhs -3 +12
>     M ./compiler/parser/Lexer.x -2 +32
>     M ./docs/users_guide/flags.xml +7
>     M ./docs/users_guide/using.xml +12

Woo hoo!