reduce debug verbosity
consolidate duplicated distance calculations
fix Linux cmath include
fix coverity issues
fix potential resource leak
flush less often to disk
Fix typos
Display number threads that are really used
Merge pull request #1002 from TheMarex/small-fixes

Small fixes
fix twisted conversion, fixes #1000
activate C+11 flags by default
activate C+11 flags by default
bump builds on travis to gcc/g++ 4.7
add ppa quietly
pick up g++-4.7 thru environment variable
pick up g++-4.7 thru cmake variable
bump min boost version to 1.49, install from ppa
install libboost 1.49 explicitly on travis
install all libboost 1.49 explicitly on travis
install all libboost 1.49 more explicitly on travis