Disable OpenSSL

It doesn't compile with Go 1.8+ (for iOS), and we've nearly replaced its functionality anyway.

MobileLibrary/iOS/PsiphonTunnel/PsiphonTunnel/PsiphonTunnel.m

@@ -311,7 +311,7 @@
 
     config[@"DeviceRegion"] = [PsiphonTunnel getDeviceRegion];
     
-    config[@"UseIndistinguishableTLS"] = [NSNumber numberWithBool:TRUE];
+    config[@"UseIndistinguishableTLS"] = [NSNumber numberWithBool:FALSE];
     
     // Get the location of the root CAs file in the bundle resources.
     NSURL *rootCAsURL = [[NSBundle bundleForClass:[self class]] URLForResource:@"rootCAs" withExtension:@"txt"];

MobileLibrary/iOS/build-psiphon-framework.sh

@@ -42,7 +42,7 @@ FRAMEWORK_BINARY="${INTERMEDIATE_OUPUT_DIR}/${INTERMEDIATE_OUPUT_FILE}/Versions/
 
 PRIVATE_PLUGINS_TAG=""
 if [[ ${FORCE_PRIVATE_PLUGINS} == true ]]; then PRIVATE_PLUGINS_TAG="PRIVATE_PLUGINS"; fi
-BUILD_TAGS="OPENSSL IOS ${PRIVATE_PLUGINS_TAG}"
+BUILD_TAGS="IOS ${PRIVATE_PLUGINS_TAG}"
 
 LIBSSL=${BASE_DIR}/OpenSSL-for-iPhone/lib/libssl.a
 LIBCRYPTO=${BASE_DIR}/OpenSSL-for-iPhone/lib/libcrypto.a