Fix building 2.4 snippets
Fix building 2.4 snippets

2.1-2.3 snippets are hard to build, but shouldn't change now.

Fixes #1198.

malcolmr/nodatime,jskeet/nodatime,malcolmr/nodatime,malcolmr/nodatime,nodatime/nodatime,BenJenkinson/nodatime,BenJenkinson/nodatime,malcolmr/nodatime,nodatime/nodatime,jskeet/nodatime