Document updates from wiki.

PR#3071

The primary changes made are:
- Updates to the "NAME" section of many pages to correctly reflect the
functions defined on those pages. This section is automatically parsed
by the util/extract-names.pl script, so if it is not correct then
running "man" will not correctly locate the right manual pages.
- Updates to take account of where functions are now deprecated
- Full documentation of the ec sub-library
- A number of other typo corrections and other minor tweaks