Merge pull request #6 from octabrain/master

Template for all directory operations
Merge pull request #7 from octabrain/master

Move testfs_dir_entry struct to correct file
changed raw_inode to *raw_inode in inode_iget, so it can be assigned to inode->i_private, and used outside of this function
added functionality to testfs_readdir
added type to testfs_dir_entry
added inode_get_data_block_num to inode.h and inode.c
Implement directory browsing for root directory

- Update format command to write root directory block
- Read directory block size from inode
- Parse the directory data block in one call