Add labelling feature to report colorization

[rschwietzke]

Our report colorization rules have a feature to go for the name by using a regexp, such as:

com.xceptance.xlt.reportgenerator.requests.table.colorization.checkout.matching = ^Checkout(?!PlaceOrder|BillingOrder)

It would be great to extend that by allowing to use the label or label and name, e.g:

com.xceptance.xlt.reportgenerator.requests.table.colorization.checkout.matching = ^Checkout(?!PlaceOrder|BillingOrder)
com.xceptance.xlt.reportgenerator.requests.table.colorization.checkout.matching.label = ordering

You have to specify either the name or the label but you can also define both, when one likes.

To make things nicer but don't break compatibility, we may introduce ...matching.name but still support the old format. If both are specified, matching.name takes precedence over just matching.

See #478