org-element: Fix paragraph parsing

* lisp/org-element.el (org-element-paragraph-parser): Small fixes to
  paragraph parsing.
Merge branch 'maint'
org-element: Fix d003d56eaf5ffb8c2106ef69cbbc6bbee57b7e00

* lisp/org-element.el (org-element-paragraph-parser): Use
  `org-match-string-no-properties'.
Merge branch 'maint'
org-element: Fix bug in `org-element-at-point'

* lisp/org-element.el (org-element-at-point): Return correct element
  when point is on a blank line just below a headline.
* testing/lisp/test-org-element.el: Add test.
Merge branch 'maint'
org-element: Fix footnote definition parsing

* lisp/org-element.el (org-element-footnote-definition-parser): Fix
  value for :contents-begin when first line of footnote definition is
  empty besides the label.
* testing/lisp/test-org-element.el (test-org-element/footnote-definition-parser):
  Add test.
Merge branch 'maint'
org-element: Fix af9c0fbf9143883ce31478a137a60cc69428d4d4
* lisp/org-element.el (org-element-at-point): Fix commit
  af9c0fbf9143883ce31478a137a60cc69428d4d4.
Merge branch 'maint'
ox-confluence: Fix void "external" variable

* contrib/lisp/ox-confluence.el (org-confluence-export-as-confluence):
  Fix argument name.

Reported-by: Chris Lowis <chris.lowis@gmail.com>
Merge branch 'maint'
Add amsmath as a global LaTeX dependency

* org.el (org-format-latex-header): Remove amsmath.
(org-latex-default-packages-alist): Remove amstext and add amsmath.

This increases consistency between LaTeX exports and LaTeX preview
snippets.
Remove eucal package for LaTeX fragments

* org.el (org-format-latex-header): Remove eucal.

With amsmath loaded eucal (basically) only provides an alternative
typeface to \mathcal{.}
Allow M-RET to insert items within drawers

* lisp/org.el (org-meta-return): Allow M-RET to insert items within
  drawers.  Rewrite function.

This patch also allows a user to insert a headline within a drawer,
which will basically break it.  The point is to leave user responsible
for his editing actions.
Add ERTs for org-meta-return

* testing/lisp/test-org.el (test-org/meta-return): New `ert-deftest'
to test `org-meta-return'.