Added default rule '*'.

Added default rule '*'.

Usage:
                  * { /* C/C++ code */ }
    <c1, ..., cN> * { /* C/C++ code */ }
    <*>           * { /* C/C++ code */ }

Default rule violates rule order: no matter where it stands
(before all rules, in the middle, or after), it's the last
rule which will be applied.