Add cache(int capacity) to Observable
Revert "CompositeException does not mutate nested exceptions by attaching stacks, but instead"

This reverts commit f4ae92aa624923e9a632fb677730a2d6e04595e5.
Remove cycles in CompositeException
Merge pull request #1431 from tomrozb/composite-exception

CompositeException fix for Android
Merge pull request #1393 from gliptak/cachehint

Add cache(int capacity) to Observable
Add perf tests for cache(1) variant
Javadocs for cache operator
Merge pull request #1467 from benjchristensen/cache-docs

Javadocs for cache operator
remove javadoc warnings from cache(); add @since annotation to cache(b)
Increasing timeout

Using low timeout values causes non-determinism in some build environments.
javadocs: add missing @see links; correct broken link URLs; standardize formatting/capitalization/punctuation
ToList operator needs to ignore backpressure
Update CONTRIBUTING.md

updating the date.
Merge pull request #1469 from mattrjacobs/fix-tolist-backpressure

ToList operator needs to ignore backpressure
Add test of backpressure to OperatorAll
OperatorAny needs to handle backpressure
Merge pull request #1472 from mattrjacobs/add-unit-test-to-operator-all

Add test of backpressure to OperatorAll
Merge pull request #1473 from mattrjacobs/handle-backpressure-in-any-operator

OperatorAny needs to handle backpressure
Ignore backpressure for OperatorToObservableSortedList
Merge pull request #1474 from mattrjacobs/ignore-backpressure-operator-tosortedlist

Ignore backpressure for OperatorToObservableSortedList