Ratio: merge from trunk

svn path=/branches/release/boost/ratio/; revision=80406
Ratio: merge 80896

svn path=/branches/release/boost/ratio/; revision=80920
Thread: Merge 80946,80947

svn path=/branches/release/boost/ratio/; revision=80963
Ratio: merge from trunk 1.53

svn path=/branches/release/boost/ratio/; revision=81665
Ratio: warning removal

svn path=/branches/release/libs/ratio/; revision=82016