ISiTGR: Testing deviations from GR at cosmological scales including
  dynamical dark energy, massive neutrinos, functional or binned
  parametrizations, and spatial curvature
  We introduce a new version of the Integrated Software in Testing General
Relativity (ISiTGR) which is a patch to the software CAMB and CosmoMC. ISiTGR
is intended to test deviations from GR at cosmological scales using
cosmological data sets. While doing so, it allows for various extensions to the
standard flat $\Lambda$CDM model. In this new release, we have support for the
following: 1) dynamical dark energy parametrizations with a constant or
time-dependent equation of state; 2) a consistent implementation of anisotropic
shear to model massive neutrinos throughout the full formalism; 3) multiple
commonly-used parametrizations of modified growth (MG) parameters; 4)
functional, binned and hybrid time- and scale-dependencies for all MG
parameters; 5) spatially flat or curved backgrounds. ISiTGR is designed to
allow cosmological analyses to take full advantage of ongoing and future
surveys to test simultaneously or separately various extensions to the standard
model. We describe here the formalism and its implementation in the CMB code,
the Integrated Sachs-Wolfe (ISW) effect, and the 3x2 point statistics. Next, we
apply ISiTGR to current data sets from Planck-2018, Planck-2015, Dark Energy
Survey YR1 release, Baryonic Acoustic Oscillations (BAO), Redshift Space
Distortions (BAO/RSD) from the BOSS Data Release 12, the 6DF Galaxy Survey and
the SDSS Data Release 7 Main Galaxy Sample, and Supernova from the Pantheon
compilation, joint SNLS/SDSS data analysis and the Hubble Space Telescope. We
derive constraints on MG parameters for various combinations of the five
features above and find that GR is consistent with current data sets in all
cases. The code is made publicly available at
\url{https://github.com/mishakb/ISiTGR}.
