public boolean contains(final String var) {
        return variablesSet.containsKey(var);
    }
Encapsulates a {@link VariableMap} but adds semantic of a list to it
(e.g. it includes and maintains ordering).
<br>
It also maintains modification state and provides hooks for loading and saving a Variable Lists state e.g. for persistence (load-from/store-to DB)
main/src/main/java/cgeo/geocaching/utils/formulas/VariableList.java