[ADAM-1486] Respect validation stringency if BAM header load fails.

[fnothaft]

Resolves #1486.

[AmplabJenkins]

Test FAILed.
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Build result: FAILURE

[...truncated 16 lines...] > /home/jenkins/git2/bin/git rev-parse origin/pr/1525/merge^{commit} # timeout=10 > /home/jenkins/git2/bin/git branch -a --contains b24b42ea4e2bb964cc9bc2467d27c04766d88a6d # timeout=10 > /home/jenkins/git2/bin/git rev-parse remotes/origin/pr/1525/merge^{commit} # timeout=10Checking out Revision b24b42ea4e2bb964cc9bc2467d27c04766d88a6d (origin/pr/1525/merge) > /home/jenkins/git2/bin/git config core.sparsecheckout # timeout=10 > /home/jenkins/git2/bin/git checkout -f b24b42ea4e2bb964cc9bc2467d27c04766d88a6dFirst time build. Skipping changelog.Triggering ADAM-prb ? 2.3.0,2.11,1.6.1,centosTriggering ADAM-prb ? 2.6.0,2.10,1.6.1,centosTriggering ADAM-prb ? 2.3.0,2.11,2.0.0,centosTriggering ADAM-prb ? 2.3.0,2.10,2.0.0,centosTriggering ADAM-prb ? 2.6.0,2.11,2.0.0,centosTriggering ADAM-prb ? 2.6.0,2.10,2.0.0,centosTriggering ADAM-prb ? 2.3.0,2.10,1.6.1,centosTriggering ADAM-prb ? 2.6.0,2.11,1.6.1,centosADAM-prb ? 2.3.0,2.11,1.6.1,centos completed with result FAILUREADAM-prb ? 2.6.0,2.10,1.6.1,centos completed with result FAILUREADAM-prb ? 2.3.0,2.11,2.0.0,centos completed with result FAILUREADAM-prb ? 2.3.0,2.10,2.0.0,centos completed with result FAILUREADAM-prb ? 2.6.0,2.11,2.0.0,centos completed with result FAILUREADAM-prb ? 2.6.0,2.10,2.0.0,centos completed with result FAILUREADAM-prb ? 2.3.0,2.10,1.6.1,centos completed with result FAILUREADAM-prb ? 2.6.0,2.11,1.6.1,centos completed with result FAILURENotifying endpoint 'HTTP:https://webhooks.gitter.im/e/ac8bb6e9f53357bc8aa8'
Test FAILed.

[fnothaft]

Helps to include the new test file...

[coveralls]

Coverage remained the same at 82.015% when pulling 94e8bd6 on fnothaft:issues/1486-bam-header-load-error into 18191f9 on bigdatagenomics:master.

[AmplabJenkins]

Test PASSed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/ADAM-prb/2000/
Test PASSed.

[heuermh]

Thank you, @fnothaft!