Use /bigobj only for bslstl
Use /bigobj only for bslstl

bslstl_hashtable's test driver is the only file that requires to be
compiled with the /bigobj flag using Visual Studio.

bloomberg/bde,dbremner/bde,idispatch/bde,che2/bde,dbremner/bde,dharesign/bde,idispatch/bde,bloomberg/bde,apaprocki/bde,minhlongdo/bde,osubboo/bde,che2/bde,dbremner/bde,bloomberg/bde,bowlofstew/bde,saxena84/bde,bloomberg/bde,idispatch/bde,osubboo/bde,che2/bde,saxena84/bde,apaprocki/bde,mversche/bde,saxena84/bde,bloomberg/bde,minhlongdo/bde,bowlofstew/bde,osubboo/bde,saxena84/bde,bowlofstew/bde,dharesign/bde,dharesign/bde,mversche/bde,mversche/bde,apaprocki/bde,mversche/bde,idispatch/bde,dbremner/bde,che2/bde,osubboo/bde,dharesign/bde,apaprocki/bde,minhlongdo/bde,bowlofstew/bde,minhlongdo/bde,apaprocki/bde