Convert strain name to its group name e.g. 'Bacteroides.1' becomes 'Bacteroides' updated (Dec 2019) so that MFG names can contain dots
getGroupName(xname, microbeNames)
xname
: a string (may be strain name or something else)microbeNames
: vector of strings of microbial group namesgroup name (string) if xname is a strain name. If xname is not a the name of a strain it will simply return xname unchanged.