Adding alt attributes to img tags in javadocs to avoid occasional build issues
minor javadoc improvements
Fix Merge Bug

Working on https://github.com/Netflix/RxJava/issues/1420
Merge pull request #1442 from benjchristensen/merge-bug

Merge Bug
Infinite request with Long.MAX_VALUE instead of -1

Migrating to this after discussions at https://github.com/reactive-streams/reactive-streams/issues/62
Merge pull request #1443 from benjchristensen/request-long-max-value

Infinite request with Long.MAX_VALUE instead of -1
[Gradle Release Plugin] - pre tag commit:  '0.20.0-RC1'.
[Gradle Release Plugin] - new version commit:  '0.20.0-RC2-SNAPSHOT'.
Version 0.20.0-RC1
first pass at javadocs for new backpressure stuff