Added possibility for upload to Duet

Further changes:
- Added new configuration option Host Type
- Added abstract base class for future printer hosts
- Moved location of upload dialog (also made it a little bit more configureable)
- added possibility to send file via postfield instead a new frame

xs/src/slic3r/Utils/Duet.hpp

@@ -0,0 +1,46 @@
+#ifndef slic3r_Duet_hpp_
+#define slic3r_Duet_hpp_
+
+#include <string>
+#include <wx/string.h>
+
+#include "PrintHost.hpp"
+
+
+namespace Slic3r {
+
+
+class DynamicPrintConfig;
+class Http;
+
+class Duet : public PrintHost
+{
+public:
+	Duet(DynamicPrintConfig *config);
+
+	bool test(wxString &curl_msg) const;
+	wxString get_test_ok_msg () const;
+	wxString get_test_failed_msg (wxString &msg) const;
+	// Send gcode file to duet, filename is expected to be in UTF-8
+	bool send_gcode(const std::string &filename) const;
+	bool have_auto_discovery() const;
+	bool can_test() const;
+private:
+	std::string host;
+	std::string password;
+	
+	std::string get_upload_url(const std::string &filename) const;
+	std::string get_connect_url() const;
+	std::string get_base_url() const;
+	std::string timestamp_str() const;
+	bool connect(wxString &msg) const;
+	void disconnect() const;
+	bool start_print(wxString &msg, const std::string &filename) const;
+	int get_err_code_from_body(const std::string &body) const;
+	static wxString format_error(const std::string &body, const std::string &error, unsigned status);
+};
+
+
+}
+
+#endif