harness: write result files

* check result file (./result/harnessresult.txt) for true qlog,
badqlog, and fixedqlog.
* to run harness, pls install cplex and add augment
(Djava.library.path) for cplex solver. for example:
-Djava.library.path=/Users/xxx/Applications/IBM/ILOG/CPLEX_Studio126/cpl
ex/bin/x86-64_osx