LFS bugfixes and improvements (#10)

* GitHub's LFS is now supported/working with these changes
* Headers for invoking actions are now respected
* User agent is now included in all requests
* Bearer token auth is now supported (OAuth2, PAT, etc.)
* Credentials class to abstract away username/pw/token

Author: peter-esik

p4-fusion/lfs/communication/credentials.cc

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2022 Salesforce, Inc.
+ * All rights reserved.
+ * SPDX-License-Identifier: BSD-3-Clause
+ * For full license text, see the LICENSE.txt file in the repo root or https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#include "credentials.h"
+
+Credentials::Credentials()
+    : m_Type(Type::None)
+{
+}
+
+Credentials::Credentials(const std::string& username, const std::string& password)
+    : m_Type(Type::UserNameAndPass)
+    , m_Username(username)
+    , m_PasswordOrToken(password)
+{
+}
+
+Credentials::Credentials(const std::string& token)
+    : m_Type(Type::Token)
+    , m_Username()
+    , m_PasswordOrToken(token)
+{
+}
+
+Credentials::Type Credentials::GetType() const
+{
+	return m_Type;
+}
+
+const std::string& Credentials::GetUsername() const
+{
+	return m_Username;
+}
+
+const std::string& Credentials::GetPassword() const
+{
+	return m_PasswordOrToken;
+}
+
+const std::string& Credentials::GetToken() const
+{
+	return m_PasswordOrToken;
+}

p4-fusion/lfs/communication/credentials.h

@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2022 Salesforce, Inc.
+ * All rights reserved.
+ * SPDX-License-Identifier: BSD-3-Clause
+ * For full license text, see the LICENSE.txt file in the repo root or https://opensource.org/licenses/BSD-3-Clause
+ */
+#pragma once
+
+#include <string>
+
+class Credentials
+{
+public:
+	enum class Type
+	{
+		None,
+		UserNameAndPass,
+		Token
+	};
+
+	Credentials();
+	Credentials(const std::string& username, const std::string& password);
+	Credentials(const std::string& token);
+
+	Type GetType() const;
+
+	const std::string& GetUsername() const;
+	const std::string& GetPassword() const;
+	const std::string& GetToken() const;
+
+private:
+	Type m_Type = Type::None;
+
+	const std::string m_Username;
+	const std::string m_PasswordOrToken;
+};