v0.12.0

Rimu v0.12.0

Diff since v0.11.2

Breaking release with a major rework of the user interface.
This release is a transition step where a much of the old user interface
is still there an usable but deprecated. If you get warning messages using
your scripts with this release, please follow instructions and update
your script to be ready for the next breaking release.

New user interface

• CommonSolve.solve is implemented for ProjectorMonteCarloProblem as the main entrance point
  to perform an FCIQMC calculation. Methods for solve, solve!, init are implemented.
  A report in form of a DataFrame can be returned from a simulation but the column names have changed.
• ExactDiagonalizationProblem together with the relevant solve method is a new access point for
  exact diagonalization of AbstractHamiltonians

See PR#248 for a more detailed description of the changes.

Other new features

• LatticeGeometry, PeriodicBoundaries, HardwallBoundaries and LadderBoundaries replaced with CubicGrid.
• Observables with eltype(op) <: AbstractArray are now supported in both dot and for use in AllOverlaps.
• New G2RealSpace operator, which is aware of the geometry and computes G_2 for all displacement vectors at the same time.

Deprecations

• lomc!
• targetwalkers as keyword argument to many ShiftStrategys is deprecated in favor of target_walkers
• FCIQMCRunStrategy and its subtype RunTillLastStep are deprecated.

Breaking changes

• LatticeGeometry no longer exists, PeriodicBoundaries, HardwallBoundaries and LadderBoundaries are no longer separate types. All user code should still run without modifications.
• removed TripleLogUpdate
• lomc! does not accept AbstractMatrix as argument
• new default style=IsDynamicSemistochastic() for default_starting_vector

Merged pull requests:

• Solve interface 3 (#248) (@joachimbrand)
• Exact diagonalization problem (#251) (@joachimbrand)
• Rework Geometry, add new G2 correlator (#254) (@mtsch)
• Bump julia-actions/cache from 1 to 2 (#256) (@dependabot[bot])
• Allow computing estimators directly on a PMCSimulation (#257) (@mtsch)
• Feature/rework mpi example (#258) (@joachimbrand)
• New communication strategy: AllToAll (#260) (@mtsch)
• CompatHelper: bump compat for KrylovKit in [weakdeps] to 0.8, (keep existing compat) (#267) (@github-actions[bot])
• Breaking changes before v1.0 release (#268) (@joachimbrand)
• Make it easier to run continuation runs (#272) (@mtsch)