mcprofile allows you to calculate signed root deviance profiles for linear combinations of parameters in a glm. Based on these profiles, multiplicity adjusted p-values and simultaneous confidence intervals controlling the family-wise error rate are calculated.
# You can install mcprofile from CRAN by
install.packages("mcprofile")
# Or the the development version from GitHub:
# install.packages("devtools")
devtools::install_github("daniel-gerhard/mcprofile")