Merge pull request #572 from uwescience/jwang_variousFixes

Jwang various fixes
MyriaApiException: create new RuntimeException to wrap cause for Java

The current method was conveying the response to the user, but was not
keeping the explanation in the throwable itself for presentation in
Java exception toString() functions.
a test can trigger the bug.
bug fix.
Merge pull request #576 from uwescience/shumo_fix_rowIndices_arity_bug_in_leapfrog

fix rowIndices arity bug in LeapFrog
Merge branch 'master' into jwang_refactorQueryEncoding