Release 1.1.8 preparations

[akarnokd]

Version 1.1.8 - July 23, 2016 (Maven)

Bugfixes

• Pull 4209: merge/flatMap to keep scalar/inner element relative order.
• Pull 4215: Fix assembly tracking replacing original exception.
• Pull 4229: fix replay() retaining reference to the child Subscriber

[stevegury]

👍

[zsxwing]

👍

[artem-zinnatullin]

👍

Can somebody please take a look at #4220? @akarnokd and I have different opinions there, would be great to hear someone else's thoughts.

[akarnokd]

Closing via 2284d4f