openssl: the preliminary version we are currently targetting for openssl

Conflicts:
	project/BuildSettings.scala
openssl: add option to disable Tls v1.1 and v1.2

Because you may not be able to talk to a Java 7 server which has
this bug:

http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7031830
openssl: proper support for enabling ssl
(cherry picked from commit e7a6bba800e84641463585f5860e8303a62a61f6)

Conflicts:
	spray-openssl/src/test/scala/spray/io/openssl/OpenSslSpecs.scala
openssl: make sure to regard ssl enabling tag for http client connections
(cherry picked from commit 8b419ec73539827c533ec2eec704fd0c5a8e85c7)
openssl: decrease lock contention when dealing with global refs
(cherry picked from commit 1aac54ed0b257028437936c8ad887effed2e11ed)
openssl: syntax
(cherry picked from commit ca93141e38cbfc5d1dfb73035353e18afaec3005)