Nbodykit

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* :issue:`555,556`: Impove dask interpolation in Catalog.save.
* :issue:`557`: Use dask's gufunc for sky transforms
* :issue:`558`: Note the unit of HaloRadius (proper, not comoving. bite me)
* :issue:`561`: Allow setting the position column in 2PCF.
* :issue:`563`: RedshiftHistogram extrapolates to zero rather than any number.
* :issue:`564`: Fix missing compensations with Multi-species meshes.
* :issue:`565`: add keyward header to HDFCatalog for reading additional meta data
* :issue:`566`: fix a bug sorting on float32, and add a persist method to Catalog.
* :issue:`567`: suppress redundant output in convpower.

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* :issue:`544,549`: Use dask.store to save a catalog.
* :issue:`545`: Fix shotnoise estimation of weighted to_mesh() calls.
* :issue:`546`: Fix IndexError in painting during throttling.
* :issue:`547`: Update docrep
* :issue:`548`: Fix many deprecation warnings
* :issue:`550`: Documentation updates
* :issue:`553`: Fix error in TPCF module when there is only 1 bin.

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* :issue:`543`: Further performance improvements on catalog slicing.
* :issue:`542`: The IO module shall make sure buffer is c-contiguous before reshaping
* :issue:`541`: Allow setting cartesian / sphericial transformation reference frame
* :issue:`540`: Allow not saving the header in Catalog.save
* :issue:`539`: Allow non-uniform redshifts in halo property transformations.
* :issue:`538`: Stop gathering catalog to a single rank in HaloCatalog
* :issue:`537`: Use numpy.sum for summing of integers.
* :issue:`536`: Fix boxsize mismatch comparision in pair counters.
* :issue:`535`: Improve working with a dask cluster.
* :issue:`532`: Improve speed of slicing of a catalog.
* :issue:`531`: Additional throttling during painting.
* :issue:`530`: Use setuptools (need to change conda-build-bccp recipe)
* :issue:`529`: Add kmax(rmax) to FFTPower, FFTCorr, ConvPower.
* :issue:`528`: Add dataset= to Catalog.save, deprecate datasets=[]

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* :issue:`519`: Rework the class hierarchy of Catalogmesh.
* :issue:`526`: Reduce the paint size for systems with lower mem per core
* :issue:`527`: Aggregate attrs of header and the main datasets.

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* :issue:`518`: Rework CurrentMPIComm
* :issue:`521`: Fix OOM errors with dask >= 0.19.0

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* :issue:`509`: Fix auto detection of f8 type in Gadget1 file reader
* :issue:`513`: Ignore divide errors.
* :issue:`516`: Fix several bugs in three point function
* :issue:`517`: Improve compatibility with numpy 1.15.x's new indexing convention.