Merge branch 'refs/heads/t/manual'

A couple of patches which merge the contents of the overview.pdf file
into the user manual. After this, the documentation no longer depends
on dia.

Cooking for six weeks.

* refs/heads/t/manual:
  manual: Expand description of para_play.
  manual: Omit level 3 headers from table of contents.
  manual: Combine overview.pdf and the user manual.
  manual: Remove text about permissions of /var/paraslash.
  manual: Correct format of para_client help output.
  manual: Add lopsub installation instructions to quick start.

diff --combined NEWS.md
index 60b942389ffe1a7d71a61ced088965995548d416,60b942389ffe1a7d71a61ced088965995548d416..313446f82956fd1f344ee483a45dcef6d9436adb
--- 1/NEWS.md
--- 2/NEWS.md
+++ b/NEWS.md
@@@ -1,6 -1,6 +1,13 @@@
  NEWS
  ====
  
++------------------------------------------------
++0.6.1 (to be announced) "hyperbolic correlation"
++------------------------------------------------
++
++- The contents of overview.pdf have been integrated into the user
++  manual.
++
  -------------------------------
  0.6.0 (2017-04-28) "fuzzy flux"
  -------------------------------