Adds opf_checkpoint_test and related experiment files and data.
Update README to include references to wiki installation instuctions and examples.
remove old Cells2 class

this was unused
remove unused code OLD_ALGORITHM

this #ifdef'ed code was unused
Merge pull request #296 from scottpurdy/tests

Adds opf_checkpoint_test and related experiment files and data.
Merge pull request #299 from scottpurdy/readme

Update README to include references to wiki installation instuctions and...
Merge branch 'master' into big-mem