[FL-1791] Flipper file format (#740)

* Lib: new flipper file format library
* Lib: flipper file format cpp wrapper
* Storage: simple function for remove file and check error
* iButton app: remove file worker, use new flipper file format instead
* Dialogs: storage error message
* Storage: simple function for mkdir and check error
* iButton app: error messages
* Libs: update makefile
* RFID app: remove file worker, use new flipper file format instead
* Flipper File: library documentation

Co-authored-by: Aleksandr Kutuzov <alleteam@gmail.com>

lib/toolbox/flipper-file-cpp.h

@@ -0,0 +1,41 @@
+#pragma once
+#include "flipper-file.h"
+
+class FlipperFileCpp {
+private:
+    FlipperFile* file;
+
+public:
+    FlipperFileCpp(Storage* storage);
+    ~FlipperFileCpp();
+
+    bool open_read(const char* filename);
+
+    bool new_write(const char* filename);
+
+    bool close();
+
+    bool read_header(string_t filetype, uint32_t* version);
+
+    bool write_header(string_t filetype, const uint32_t version);
+
+    bool write_header_cstr(const char* filetype, const uint32_t version);
+
+    bool read_string(const char* key, string_t data);
+
+    bool write_string(const char* key, string_t data);
+
+    bool write_string_cstr(const char* key, const char* data);
+
+    bool read_uint32(const char* key, uint32_t* data);
+
+    bool write_uint32(const char* key, const uint32_t data);
+
+    bool write_comment(string_t data);
+
+    bool write_comment_cstr(const char* data);
+
+    bool write_hex_array(const char* key, const uint8_t* data, const uint16_t data_size);
+
+    bool read_hex_array(const char* key, uint8_t* data, const uint16_t data_size);
+};