Updated and refactored code

- Added `doxygen` API documentation with theme
- Added error-compatible logging function
- Added more error codes
- Added `non_copyable` function
- Added test function from exporting package list
- Changed how errors are handled with returns
- Change `gdpm remote` API to reflect `git`
- Change most functions to accept a vector of arguments instead of a single parameter
- Updated `.gitignore` and `README.md` files
- Fixed issue with `gdpm export` command crashing

include/types.hpp

@@ -0,0 +1,23 @@
+#pragma once
+
+namespace gdpm{
+	/*
+	Base class to prevent derived class from creating copies.
+	*/
+	class non_copyable{
+	public:
+		non_copyable(){}
+	
+	private:
+		non_copyable(const non_copyable&);
+		non_copyable& operator=(const non_copyable&);
+	};
+
+	/*
+	Base class to prevent derived classes from moving objects.
+	*/
+	class non_movable{
+		non_movable(const non_movable&) = delete;
+		non_movable(non_movable&&) = delete;
+	};
+}