[info] factor out parsing of [] so it can be used to parse other strings
[info] [] parsing can use the new ReplaceString() function
[info] adds [] to info labels, allowing skinners to specify a number. Required as by default numbers are taken as a reference into localized strings.  In future, this will be dropped in favour of [] only being used as this will benefit translation
Merge pull request #3919 from jmarshallnz/number_labels

Allow use of $NUMBER[] to specify a number in XML tags