Fixes #115.

Cache the values file_index_map and sorted_files.
Untabify and kill trailing whitespace
Merge branch 'file-listing-improvements' of https://github.com/Eijebong/transmission-remote-cli
More untabifycation
Merge branch 'file-listing-improvements'
Merge branch 'master' of http://github.com/fagga/transmission-remote-cli