To uninstall libboost-date-time1.49.0 just follow these instructions.
sudo apt-get remove libboost-date-time1.49.0
This will remove just the libboost-date-time1.49.0 package itself.
sudo apt-get remove --auto-remove libboost-date-time1.49.0
This will remove the libboost-date-time1.49.0 package and any other dependant packages which are no longer needed.
If you also want to delete your local/config files for libboost-date-time1.49.0 then this will work.
sudo apt-get purge libboost-date-time1.49.0
Or similarly, like this libboost-date-time1.49.0
sudo apt-get purge --auto-remove libboost-date-time1.49.0
|Maintainer||Debian Boost Team <firstname.lastname@example.org>|
|Description||set of date-time libraries based on generic programming concepts|