add index_handle option to buckets
start using the logging module everywhere instead of a global verb
recursive spilling
Merge branch 'hotfix/gridspec' into develop
refactor field wrapping
add iter_times and fix __exit__ signature
use argument group for general vutil opts
p2d.py wip
bugfix single time slice
wrap h5py dataset so a shload of hdf5 file handles aren't open for the lifetime of the program
initial p2d / multiplot implementation

this is still not entirely feature complete with respect to the old p2d
unsharing axes is not supported by mpl yet
Merge branch 'feature/p2d' into develop
Version bump to 0.42

xdmf files don't keep h5py files open for duration of program
add iterator over temporal datasets with slicing
very primitive p2d.py script
Merge branch 'release/0.42'