Merge pull request #147 from jix/smtbmc-keepgoing

Support and tests for smtbmc `--keep-going`

diff --cc sbysrc/sby_engine_smtbmc.py
Simple merge

diff --cc tests/.gitignore
index 120675bec4354855a2ba9fe51cff81368d3f05b8,86d3851aaf89cdb7e4f1dad49f9beff9dee019f6..23d000849d886622aefc2e48115fb37ed990da18
--- 1/tests/.gitignore
--- 2/tests/.gitignore
+++ b/tests/.gitignore
@@@ -8,6 -8,6 +8,7 @@@
  /redxor*/
  /stopfirst*/
  /junit_*/
+ /keepgoing_*/
  /submod_props*/
  /multi_assert*/
 +/aim_vs_smt2_nonzero_start_offset*/