Fix the bug that 'flatMap' swallows OnErrorNotImplementedException
Fix head/tail false sharing issues.
Javadoc changes to help fix #1322
Merge pull request #1374 from nitsanw/master

Fix head/tail false sharing issues
Merge pull request #1367 from zsxwing/swallow-error

Fix the bug that 'flatMap' swallows OnErrorNotImplementedException