add foam
Merge pull request #12 from sciunto/foam

bubble velocity field in foams.
Make titles; clean up markdown.
More tweaks for compatiblity with sphinx.
Expand and update streaming, FramewiseData.
Add uncertainty notebook.
Edits for doc overhaul.
Revert to nbformat v3.
Convert other v4 notebook.
Refine header levels.
Merge pull request #14 from danielballan/edit-for-doc

Edit for doc