addBeforFileExtension: Add text before file-extension
Description
This function helps changing charater srings like file-names and allows adding the character vector 'add'
(length 1) before the extension (defined by last '.') of the input string 'x'.
Used for easily creating variants/additional filenames but keeping current extension.
Usage
addBeforFileExtension(x, add, sep = "_")
Arguments
x
main character vector
add
character vector to be added
sep
(character) separator between 'x' & 'add' (character, length 1)