# 4.7.18
 -- added imp_var and imp_suffix to irmi, so it is more consistent with the other functions
# 4.7.17
 -- added parameter addRF, only RF to kNN, to use random forest in combination with kNN
# 4.7.12
 -- testthat package used for all tests
 -- added travis automatically building/checking
 -- covr for code coverage (vis functions are currently not covered by any tests)
 -- new imputation function matchImpute for faster imputation randomly by group
#4.7.1
 -- new imputation function 'matchImpute' for imputing random within groups
#4.6.1 
 -- use ordered logistic regression for ordinal variables in irmi
#4.6.0
 -- new option for kNN 'weightDist' to use the distances for the k nearest neighbours as weights
 -- Bytecompile is enabled
 -- The R function which.minN is not used anymore, instead there is a C++ function, kNN is now about 1.6 times faster on
    a replication (100x) of the sleep dataset
#4.4.0
 -- bugfix  wrong observations marked as imputed in the hotdeck function
 -- random sorting is now used in hotdeck if no ord_var is defined
#4.2.3
 -- bugfix for the computation of distances for ordered variables
#4.2.1
 -- new option for kNN 'useImputedDist' if the imputed values of a variable should be used in subsequent imputation of another variable.
#4.2.0
 -- bug fixed in irmi with newer version of nnet (multinom) and if residual scale can not be computed (noise)
 -- Improvement Gower dist with only missing values in data.x or data.y
#4.1.0
 -- new parameter modelFormula in irmi
 -- bug fixes in irmi
 -- updated hotdeck based on data.table -> faster and quite stable
 -- bug fix if range of a variable is 0 in gower.dist
 -- small fixed kNN
#4.0.1
 -- small bugfix for using makeNA in kNN
 -- "Nothing to impute"-Error is now a warning
 -- imp_var now updates existing TF imp_vars (with warning)
 
#4.0.0
 -- new pacakge VIMGUI contains all GUI functions
 -- vignettes moved to VIMGUI
 -- new imputation function regressionImp
 -- roxygen style comments -> help files