With this change it is possible to dump a folder to stdout as a tar. The
It can be used just like the normal dump command:
`./restic dump fa97e6e1 "/data/test/" > test.tar`
Where `/data/test/` is a a folder instead of a file.
This commit refactors the documentation according to my proposal in #1273
and the discussion I had with fd0 on IRC.
The bits from the manual that I could not immediately put into the new
structure are contained in manual_rest.rst Anything else is still there,
nothing has been deleted.
I changed the heading markup to follow the convention used in Python’s
Style Guide for documentation, this convention is explained in a comment
at the top of every file.
I also added a paragraph on installing restic on Debian.
