TODO

 - add an --insecure option as by default, SSL should always be used
 - add debug printing using better means than stderr printfs
 - fuse can log to syslog
 - write documentation
 - create read-only offline mode
 - allow to control disk cache size
 - replace atol and atoi with strtol with proper error checking
 - find permanent solution for --no-as-needed on Ubuntu
 - make buckets ordered so that queries and insertions can be done using
   bisection
 - make array of children of h_entry ordered for quicker member search
 - use __attribute__ ((warn_unused_result));
 - replace sizeof for key, name and hash with #define-ed values
 - use less realloc but instead only realloc to double the size when array
   gets full
 - store more efficient structure on disk (for example by making filenames
   zero terminated)
 - make h_entry more efficient in memory (for example by making filenames
   zero terminated)
 - when handling device/get_changes, make sure to only use the latest
   revision of the same file-/folderkey
 - allow different cache directory (useful for running test suite)
 - delete patches in cache that have been applied
 - after uploading a file it is immediately downloaded - instead, the existing
   local file should be used by checking the remote hash
 - add an option to only call device/get_status in configurable intervals
 - add an option to make file cache size configurable
 - write man pages
 - implement truncate (problem: zero byte files are not allowed at the remote)
 - move uploading of files from release() to flush() because the return
   value of release is ignored and because the calling close() returns
   before release() finishes (problem: zero byte files are not allowed at
   the remote)
 - create a Debian package
 - call folder/get_content in a loop until more_chunks=no because it currently
   stops at 1000 (max value for chunk_size param)
 - proper versioning of the directory cache
 - call user/get_info to populate statvfs struct for returning free space