Fixes #170
Added vphi: command not found and vtheta: command not found to derived arrays
Merge pull request #175 from pynbody/beta

Fixes #170
Attempt to fix issue #179
Nosetest for issue #179 underlying problem
Correct behaviour when interpolated images are actually only using one level of interpolation - issue #172
Merge pull request #180 from pynbody/issue_179

Fix for issue 179 - new SimArrays based on IndexedSimArrays forget their context
Revert erroneous change to upper limit of smooth_range
Merge pull request #181 from pynbody/issue_172

Correct behaviour when interpolated images are actually only using one level
Fix issue #182
Remove -ftree-vectorizer-verbose=1 from cc arguments: latest versions of clang give an error as they do not recognize this flag
Second attempt to fix issue #182 - Profile fails when some bins are empty and derived arrays are required
Move all SPH content into sph submodule
Improve spherical image rendering using latest version of healpy
Remove obsolete documentation
Merge pull request #184 from pynbody/sph_updates

Updates to SPH module - package restructured and spherical image rendering improved
Add log_interpolation option to PowerSpectrumCAMBLive
Add context managers for translations
Generalize transformations module to allow use without with statement, and to implement rotations.
Expand use of transformations to analysis submodules