Feature/lcd buffering

[niwciu]

Added fallowing feature/functions to library API:

void lcd_buf_cls(void);
void lcd_buf_char(const char c);
void lcd_buf_locate(enum LCD_LINES y, enum LCD_COLUMNS x);
void lcd_buf_str(const char *str);
void lcd_update(void);

void lcd_buf_int(int val, uint8_t width, enum alignment alignment);
void lcd_buf_hex(int val, uint8_t width, enum alignment alignment);
void lcd_buf_bin(int val, uint8_t width);