Support filtering by list with wildcard

[danielhuppmann]

A useful feature (from a pyam-user-perspective) is to filter by a list with wildcards, e.g., get all variables from the Primary-Energy and Emissions category. In pyam, this could be done using

df.filter(variable=["Primary Energy|*", "Emissions|*"]

The current filter-structure allows only either filtering by a list (using equality) or a single wildcard string.