Add package blockTools

[ugroempi]

The package author sent a request. I believe that the package was part of the task view earlier, and presumably got kicked out due to archiving on CRAN.

A short description:

Causal inference in social and biomedical research often relies on estimates from randomized experiments. blockTools offers functionality for designing, conducting, and analyzing aspects of randomized experiments. "Blocking" involves sorting experimental units into homogeneous groups prior to randomization. Randomization then occurs within those groups. blockTools allows experimentalists to easily

• block experimental units using many background covariates simultaneously (including continuous ones)
• incorporate substantive knowledge via weights on variables
• randomly assign blocked units to treatment conditions within blocks
• detect possible interference between treatment and control units ("contamination", or "spillovers")
• quickly write tables of proposed blocks or experimental assignment protocols to .tex or .csv files

[ugroempi]

re-included the package, re-activating the old entry plus (very) little more detail