A regular expression used to parse the output of the Version Check Command. Capturing group(s) must be used to identify the version itself.

e.g. for git, the command "git --version" outputs a string of the form "git version 1.2.3" so would need a regular expression "git version ([0-9.]*)" in order to obtain the version "1.2.3".

If this is left blank (the default) then no version check will be performed.