Removed destructor from File.cpp and SD.h as it leads to unexpected close/destructed objects #814

libraries/SD/src/SD.h

@@ -31,7 +31,6 @@ class File : public Stream {
 public:
   File(SdFile f, const char *name);     // wraps an underlying SdFile
   File(void);      // 'empty' constructor
-  ~File(void);     // destructor
   virtual size_t write(uint8_t);
   virtual size_t write(const uint8_t *buf, size_t size);
   virtual int read();