Tangos

New features
* Restore support for MySQL databases (cphyc / apontzen) https://github.com/pynbody/tangos/pull/165
* Add tool to delete a named halo property https://github.com/pynbody/tangos/pull/167
* Command-line tools for searching for and removing runs in bulk (j-davies-astro) https://github.com/pynbody/tangos/pull/169

Bug fixes
* Fix small but debilitating bugs introduce into pynbody handler in previous release. These were discovered when rebuilding the tutorial. https://github.com/pynbody/tangos/pull/168
* Added integration testing to stop bugs of this type being reintroduced again https://github.com/pynbody/tangos/pull/171

Other
* Change sqlalchemy requirement to v1.4. This has a nicer API which was essential in reintroducing MySQL support. It also acts as a bridge towards v2.0 support. https://github.com/pynbody/tangos/pull/170

Bug fixes
* Fix two issues with URL generation for on-the-fly plots in web server by apontzen in https://github.com/pynbody/tangos/pull/158

Enhancements
* Improved support for Adaptahop + Ramses by Martin-Rey in https://github.com/pynbody/tangos/pull/160
* Allowing importing arrays of numbers as tangos properties by Martin-Rey in https://github.com/pynbody/tangos/pull/159
* Add ability to insist on using IDL-refined AHF catalogues by apontzen in https://github.com/pynbody/tangos/pull/120

**Full Changelog**: https://github.com/pynbody/tangos/compare/v1.3.1...v1.4.0

Bug fix

Fix an issue with using old databases due to the switch to unsigned integers to support AHF halo numbering. Databases generated with older versions of tangos could not be correctly accessed with v1.3. Version 1.3.1 should restore access to older databases. (mtremmel)

Enhancements
--------------

* Add support for using new black hole logging in Changa (mtremmel)
* Provide a safe route to accessing simulation properties inside a property calculation
* Add support for very long halo finder numbers used by some versions of AHF

Enhancements
===========

* Introduce pagination of the halo lists in the web interface
* Add support for using SVG and PDF as the plot format in the web interface (cphyc)
* Add ability to specify colour range of images in web interface (cphyc)
* Add properties `stars_shrink_center` and `gas_shrink_center` which give centers based purely on stars and gas respectively (Martin-Rey)
* Permit use of `preloop` functions (evaluated at timestep rather than halo level) when evaluating live calculations
* Various other minor improvements to the web interface

Bug fixes
=======

* Changes from using `%` to using `_` to escape slashes in filenames of simulations, fixing an ambiguity that could cause problems (j-davies-ari)
* Fixes an issue with AHF which, when run using MPI, numbers halos randomly rather than sequentially. This necessitates introducing an extra database column; tangos now distinguishes between (1) `halo_number` [tangos primary reference point] (2) `finder_id` [the ID assigned by the halo finder] (3) `finder_offset` [the 0-based offset of the halo in the finder catalogue, which may be different from `finder_id` in the case of AHF] (mtremmel)
* Fix issue 135: the timing logging could sometimes crash, if the procedure they were monitoring crashed

This version fixes poor performance of `earlier`, `earliest`, `later`, `latest` and related functionality, and fixes a bug in `find_progenitor` and `find_descendant` that was triggered when some snapshots were missing data.