README changes:

+ Documented superscript, subscript, and strikeout syntax
+ Modified description of LaTeX packages needed for markdown2pdf


git-svn-id: https://pandoc.googlecode.com/svn/trunk@743 788f1e2b-df1e-0410-8736-df70ead52e1b

README

@@ -56,15 +56,13 @@ The wrapper script `markdown2pdf` requires
   - `pandoc` (which must be in the PATH)
   - a POSIX-compliant shell
   - `pdflatex`, which should be part of any [LaTeX] distribution
-  - the [unicode] and [fancyvrb] LaTeX packages, which are included
-    in many LaTeX distributions.[^1] If your installation of LaTeX
-    does not include these packages, you will get an error (complaining
-    about missing `ucs.sty` or `fancyvrb.sty`) when you try to compile
-    a LaTeX file produced by Pandoc, or when you use the `markdown2pdf`
-    script (described below).  If this happens, install the [unicode] and
-    [fancyvrb] packages package from [CTAN].  (Get the zip file from CTAN
-    and unpack it into `~/texmf/tex/latex/`.  You may also need to run
-    `mktexlsr` or `texhash` before the files can be found by TeX.)
+  - the following LaTeX packages (available from [CTAN], if they
+    are not already included in your LaTeX distribution):
+    + `unicode` (for UTF8 characters)
+    + `fancyvrb` (for verbatim text in footnotes)
+    + `graphicx` (for images)
+    + `array` (for tables)
+    + `ulem` (for strikeout text)
 
 The wrapper script `hsmarkdown` requires only a POSIX-compliant shell.
 
@@ -72,12 +70,6 @@ The wrapper script `hsmarkdown` requires only a POSIX-compliant shell.
 [HTML Tidy]:  http://tidy.sourceforge.net/
 [`iconv`]: http://www.gnu.org/software/libiconv/
 [CTAN]: http://www.ctan.org "Comprehensive TeX Archive Network"
-[unicode]: http://www.ctan.org/tex-archive/macros/latex/contrib/unicode/
-[fancyvrb]: http://www.ctan.org/tex-archive/macros/latex/contrib/fancyvrb/
-
-[^1]: The [unicode] package allows LaTeX to process UTF-8 characters.
-[fancyvrb] allows code blocks and verbatim text to be used within
-footnotes.
 
 Using Pandoc
 ============
@@ -383,6 +375,29 @@ which allows only the following characters to be backslash-escaped:
 
     \`*_{}[]()>#+-.!
 
+Subscripts and superscripts
+---------------------------
+
+Superscripts may be written by surrounding the superscripted text by `^`
+characters; subscripts may be written by surrounding the subscripted
+text by `~` characters.  Thus, for example,
+
+    H~2~O is a liquid.  2^10^ is 1024.
+
+If the superscripted or subscripted text contains spaces, these spaces
+must be escaped with backslashes.  (This is to prevent accidental
+superscripting and subscripting through the ordinary use of `~` and `^`.)
+Thus, if you want the letter P with 'a cat' in subscripts, use
+`P~a\ cat`, not `P~a cat~`.
+
+Strikeout
+---------
+
+To strikeout a section of text with a horizontal line, begin and end it
+with `~~`. Thus, for example,
+
+    This ~~is deleted text.~~
+
 Lists
 -----
 
@@ -551,7 +566,7 @@ Simple tables look like this:
 
 The headers and table rows must each fit on one line.  Column
 alignments are determined by the position of the header text relative
-to the dashed line below it:[^2]
+to the dashed line below it:[^1]
 
   - If the dashed line is flush with the header text on the right side
     but extends beyond it on the left, the column is right-aligned.
@@ -562,7 +577,7 @@ to the dashed line below it:[^2]
   - If the dashed line is flush with the header text on both sides,
     the default alignment is used (in most cases, this will be left).
 
-[^2]:  This scheme is due to Michel Fortin, who proposed it on the
+[^1]:  This scheme is due to Michel Fortin, who proposed it on the
     Markdown discussion list: <http://six.pairlist.net/pipermail/markdown-discuss/2005-March/001097.html>
 
 The table must end with a blank line.  Optionally, a caption may be
@@ -745,7 +760,7 @@ escaped with a backslash if needed.
 If you pass the `-m` (`--asciimathml`) option to `pandoc`, it will
 embed the [ASCIIMathML] script in the resulting HTML.  This will
 cause LaTeX math to be displayed as formulas in better
-browsers.[^3]
+browsers.[^2]
 
 [ASCIIMathML]: http://www1.chapman.edu/~jipsen/asciimath.html 
 
@@ -767,7 +782,7 @@ You can also use LaTeX environments.  For example,
 Note, however, that material between the begin and end tags will
 be interpreted as raw LaTeX, not as markdown.
 
-[^3]: If you are serving several pages that use ASCIIMathML, it will be
+[^2]: If you are serving several pages that use ASCIIMathML, it will be
     more efficient to link to an external copy of `ASCIIMathML.js`
     instead of using the `-m|--asciimathml` option to embed it directly
     in web pages. To do this, get a copy of `ASCIIMathML.js` from the