Add support for updating local cache through patches

- refactor some code:
   - code handling the file cache is now in fuse/filecache.c
   - base36 and base16 encoding and decoding moved to utils/hash.c
 - mfshell: add "updates" command calling device/get_updates
 - add container class to store patch information as mfapi/patch.c
 - apicalls: store more info retrieved by file/get_info
 - apicalls: add device/get_updates
 - apicalls: add device/get_patch

utils/hash.h

@@ -21,5 +21,8 @@
 
 int             calc_md5(FILE * file, unsigned char *hash);
 int             calc_sha256(FILE * file, unsigned char *hash);
+int             base36_decode_triplet(const char *key);
+void            hex2binary(const char *hex, unsigned char *binary);
+char           *binary2hex(const unsigned char *binary, size_t length);
 
 #endif