Modularize cmake build config

Builds/CMake/deps/OpenSSL.cmake

@@ -0,0 +1,48 @@
+#[===================================================================[
+   NIH dep: openssl
+#]===================================================================]
+
+#[===============================================[
+  OPENSSL_ROOT_DIR is the only variable that
+  FindOpenSSL honors for locating, so convert any
+  OPENSSL_ROOT vars to this
+#]===============================================]
+if (NOT DEFINED OPENSSL_ROOT_DIR)
+  if (DEFINED ENV{OPENSSL_ROOT})
+    set (OPENSSL_ROOT_DIR $ENV{OPENSSL_ROOT})
+  elseif (HOMEBREW)
+    execute_process (COMMAND ${HOMEBREW} --prefix openssl
+      OUTPUT_VARIABLE OPENSSL_ROOT_DIR
+      OUTPUT_STRIP_TRAILING_WHITESPACE)
+  endif ()
+  file (TO_CMAKE_PATH "${OPENSSL_ROOT_DIR}" OPENSSL_ROOT_DIR)
+endif ()
+
+if (static)
+  set (OPENSSL_USE_STATIC_LIBS ON)
+endif ()
+set (OPENSSL_MSVC_STATIC_RT ON)
+find_package (OpenSSL 1.0.2 REQUIRED)
+target_link_libraries (ripple_libs
+  INTERFACE
+    OpenSSL::SSL
+    OpenSSL::Crypto)
+# disable SSLv2...this can also be done when building/configuring OpenSSL
+set_target_properties(OpenSSL::SSL PROPERTIES
+    INTERFACE_COMPILE_DEFINITIONS OPENSSL_NO_SSL2)
+#[=========================================================[
+   https://gitlab.kitware.com/cmake/cmake/issues/16885
+   depending on how openssl is built, it might depend
+   on zlib. In fact, the openssl find package should
+   figure this out for us, but it does not currently...
+   so let's add zlib ourselves to the lib list
+   TODO: investigate linking to static zlib for static
+   build option
+#]=========================================================]
+find_package (ZLIB)
+set (has_zlib FALSE)
+if (TARGET ZLIB::ZLIB)
+  set_target_properties(OpenSSL::Crypto PROPERTIES
+    INTERFACE_LINK_LIBRARIES ZLIB::ZLIB)
+  set (has_zlib TRUE)
+endif ()