added list_reverse example to regression test; tested both unification and pattern-matching
commented out a non-confluence rule that failed the list_reverse example
made size_t parsed consistently as a CId in both the program and specification
commented out a production which caused wierd parsing error of cil
added bidwidth attr to machine integer variables in list_pattern
list_reverse example worked for k-framework rev d5633cec
Merge pull request #46 from yilongli/java_rewrite_engine

(partially) proved the CIL list_reverse example