Change relative weekday specifications (ex: fri or -tue) to exclude today

* lisp/org.el (org-read-date-get-relative): Handle positive and
negative weekday specifications so that they don't return today.
If today is Friday, "fri" should mean next Friday. This changes
the previous behavior, which required you to specify "+2fri" in
order to mean next Friday if today was Friday. If you want to
schedule something for today, you can use ".".

* doc/org.texi (The date/time prompt): Update the documentation
to reflect the new way `org-read-date-get-relative' handles
weekdays.

TINYCHANGE
Merge branch 'master' of orgmode.org:org-mode
org.texi: remove footnote from subheading

* doc/org.texi (Agenda commands): Remove footnote from
  @tsubheading (as a macro argument it would need to be kept on a
  single line) and add a sentence with the reference instead.
Babel: avoid superfluous confirmation for internal wrapper

* lisp/ob-exp.el (org-babel-exp-results): Suppress user confirmation
  of the emacs-lisp wrapper execution around a lob call.

* lisp/ob-lob.el (org-babel-lob-execute): Suppress user confirmation
  of the emacs-lisp wrapper execution around a lob call.
org.el (org-uniquify-alist): Improve docstring

* org.el (org-uniquify-alist): Improve docstring.
org-clock.el (org-clock-select-task): Remove successive duplicates in the clock history to consider

* org-clock.el (org-clock-select-task): Remove successive
duplicates in the clock history to consider.

Thanks to Sébastien Vauban for pointing at this.
org-agenda.el (org-timeline): Handle `org-agenda-show-log'

* org-agenda.el (org-timeline): Handle `org-agenda-show-log'.

Thanks to Derek Upham for reporting this bug.
org.texi: Document Markdown export
org-agenda.el (org-agenda-entry-text-mode): Also check against regexp filters

* org-agenda.el (org-agenda-entry-text-mode): Also check
against regexp filters.