Showing a file’s history with the `log` command

[frank-lenormand]

Hi,

It’d be great to be able to run the log command on file paths as well.

Currently, the command only expects a revision/range, and I would like it to accept a file path (interactive prompt?) and provide with similar functionality provided by the following equivalent commands:

tig <path>
git log -- <path>

The resulting list of commits would be displayed in a view no different than the already existing “regular” revision/range log.

Related: #62, #101.