Configuration to disable TLS

Added configuration to dub.sdl that will disable TLS.

Author: Andrepuel

dub.sdl

@@ -15,4 +15,7 @@ configuration "with_openssl" {
 	versions "hasOpenssl"
 	dependency "openssl" version="~>1.1.4+1.0.1g"
 	lflags "-L/usr/local/opt/openssl/lib"
+}
+configuration "without_tls" {
+	platforms "osx" "windows" "linux"
 }

source/upromised/loop.d

@@ -128,9 +128,7 @@ Loop defaultLoop() {
 			} else version(hasSecurity) {
 				return Promise!TlsContext.resolved(TlsContext.init);
 			} else {
-				auto r = new Promise!TlsContext;
-				r.reject(new Exception("TLS not supported"));
-				return r;
+				return Promise!TlsContext.rejected(new Exception("TLS not supported"));
 			}
 		}
 
@@ -156,9 +154,7 @@ Loop defaultLoop() {
 							.then!Stream(() => r);
 					});
 			} else {
-				auto r = new Promise!Stream;
-				r.reject(new Exception("TLS not supported"));
-				return r;
+				return Promise!Stream.rejected(new Exception("TLS not supported"));
 			}
 		}