Update C++ build documentation to include OpenSLL dependency
This closes
@@ -14,6 +14,7 @@ Building on Linux With Autotools
Common Requirements:
* GCC, g++, autotools, automake, and libtool must be installed
+ * OpenSSL, 1.0 or later
* Java Development Kit (JDK) must be installed: https://java.com/en/download/index.jsp
* JAVA_HOME environment variable must be set pointing to Java installation directory.
* IGNITE_HOME environment variable must be set to Ignite installation directory.
