Revert "Merge pull request #172 from scj7t4/ExceptionCrash"

This reverts commit 37d775266f734d4922208a5f660891bb0f4e3bde, reversing
changes made to 94e0b4a385f6510f834f5d082952c18d2b8e0347.

Added an unexpected dependency on Boost 1.47 and POSSIBLY created
issues with the DGI's response to SIGINT. We'll leave this in master
for now but it contributes nothing useful to release.