Add job cancellation support in Hyracks.

This change also:
- cleans up JobRun;
- adds tests for job cancellation.

Change-Id: Ic26330c19c8642dd3246739b5150c4aa667c359c
Reviewed-on: https://asterix-gerrit.ics.uci.edu/1537
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
BAD: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Integration-Tests: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: Till Westmann <tillw@apache.org>
diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/testsuite.xml b/asterixdb/asterix-app/src/test/resources/runtimets/testsuite.xml
index a651833..29998fd 100644
--- a/asterixdb/asterix-app/src/test/resources/runtimets/testsuite.xml
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/testsuite.xml
@@ -6758,7 +6758,7 @@
     <test-case FilePath="load">
       <compilation-unit name="duplicate-key-error">
         <output-dir compare="Text">none</output-dir>
-        <expected-error>org.apache.hyracks.api.exceptions.HyracksException</expected-error>
+        <expected-error>Input stream given to BTree bulk load has duplicates</expected-error>
       </compilation-unit>
     </test-case>
     <test-case FilePath="load">