[O] Language identifiers

[François Pinard]

Hello, Org people.

Seeing again the (org) Languages node in the manual, I decided to check
all my #+BEGIN_SRC for language tags, which I too often improvise, for
normalizing them.  I noticed a few things, and wonder if the manual
should be amended, or if I should change my habits instead.

- I was using lower case "c" and "r", while the manual suggests
  upper case "C" and "R" instead.  Both seem to work (in Emacs at
  least).  Should the manual be amended to say that case does not
  matter?  If then, should the manual stick uniformly to lower case?

- The identifier in the left column did not work, but if I change it to
  the identifier in the right column, the content highlights (in
  Emacs).  The manual does not list it.

  | config     | conf     |
  | email      | mail     |
  | make       | makefile |
  | postscript | ps       |

- I was using "elisp" instead of "emacs-lisp" and "javascript" instead
  of "js".  Both seem to work (in Emacs at least).  If there are many
  alternate languages identifiers for a language, should the manual list
  all acceptable identifiers?

- Tag "xml" seems to work nicely (within Emacs).  The manual does not
  list it.

I wonder what "are supported" really means, in the first sentence.
Maybe the fact that Emacs supports a language tag does not mean that Org
supports it?  Maybe exporters would fail to render them nicely?  Maybe a
few more words could be added to the page for explaining what users
should expect, or not expect.  Currently, I do not know whether if the
list is missing a few identifiers, or if I'm not using them properly.

Other tiny details about the table at the beginning of this Info page.
It would be clearer if there was a separating line between the title
line and the table contents.  A vertical line separating both halves
would be welcome too, one has to take a few seconds to understand that
this is a two column table, each column itself holding two columns.
Finally, the sorted entries are presented row wise in this two column
table; the table would be easier to consult if the sorted entries were
presented column wise instead.

François