Allow users to put folders #16

An user should be able to put a folder.

When that happens, provy must:
a) Compare local to remote, file by file;
b) If file exists locally but not remotely, copy it;
c) If file does not exist locally, but exists remotely, do nothing (on risk of losing stuff);
d) If file exists on both, but md5 differ, update it;

This way users can still use templates when putting folders.