OpenSSL 1.1.0 support (#2826)

* make pre5 work

* add a blank line to make the diff happier

* 1.1.0-pre6 working

* support the changes since 1.1.0-pre6

* fixes

* add 1.1.0 to travis

* expose the symbol

* better testing for numericstring

* handle libre...

* actually use the 1.1.0 we compile

* cache the ossl-110 dir on travis

* add some newlines

* changelog entry for 1.1.0 support

* note that we test on 1.1.0

* proper skip on this test

* reorder
diff --git a/docs/installation.rst b/docs/installation.rst
index 2e1b3ae..3d10c36 100644
--- a/docs/installation.rst
+++ b/docs/installation.rst
@@ -34,6 +34,7 @@
 * ``OpenSSL 1.0.1j-freebsd``
 * ``OpenSSL 1.0.1f``
 * ``OpenSSL 1.0.2-latest``
+* ``OpenSSL 1.1.0``
 
 .. warning::
     OpenSSL 1.0.0 is no longer supported by the OpenSSL project. Cryptography