Use -u 'username:password' for basic auth in the curl request snippet

Previously, when a request was made that used basic auth, the curl
snippet would configure the authentication header with the
Base64-encoded header. This commit updates the snippet to use the
more human-friendly -u option to provide the username and password
in place of the authentication header.

Closes gh-122

spring-restdocs-core/src/test/java/org/springframework/restdocs/curl/CurlRequestSnippetTests.java

@@ -36,6 +36,7 @@ import org.springframework.restdocs.templates.TemplateResourceResolver;
 import org.springframework.restdocs.templates.mustache.MustacheTemplateEngine;
 import org.springframework.restdocs.test.ExpectedSnippet;
 import org.springframework.restdocs.test.OperationBuilder;
+import org.springframework.util.Base64Utils;
 
 /**
  * Tests for {@link CurlRequestSnippet}
@@ -44,6 +45,7 @@ import org.springframework.restdocs.test.OperationBuilder;
  * @author Yann Le Guern
  * @author Dmitriy Mayboroda
  * @author Jonathan Pearlin
+ * @author Paul-Christian Volkmer
  */
 public class CurlRequestSnippetTests {
 
@@ -257,4 +259,14 @@ public class CurlRequestSnippetTests {
 						.request("http://localhost/foo").build());
 	}
 
+	@Test
+	public void httpBasicAuthorizationHeader() throws IOException {
+		this.snippet.expectCurlRequest("get-request")
+				.withContents(codeBlock("bash").content("$ curl 'http://localhost/foo' -i -u 'user:secret'"));
+		new CurlRequestSnippet().document(new OperationBuilder("get-request", this.snippet.getOutputDirectory())
+				.request("http://localhost/foo")
+				.header(HttpHeaders.AUTHORIZATION, "Basic " + Base64Utils.encodeToString("user:secret".getBytes()))
+				.build());
+	}
+
 }