Added instructions for manual install from oxs, win packages.

INSTALL.md

@@ -7,6 +7,18 @@
   - For PDF output, you'll also need to install LaTeX.
     We recommend [MiKTeX](http://miktex.org/).
 
+  - If you'd prefer, you can extract the pandoc and pandoc-citeproc
+    executables from the MSI and copy them directly to any directory,
+    without running the installer.  Here is an example showing how to
+    extract the executables from the pandoc-1.19.1 installer and copy
+    them to `C:\Utils\Console\`:
+
+        mkdir "%TEMP%\pandoc\"
+        start /wait msiexec.exe /a pandoc-1.19.1-windows.msi /qn targetdir="%TEMP%\pandoc\"
+        copy /y "%TEMP%\pandoc\pandoc.exe" C:\Utils\Console\
+        copy /y "%TEMP%\pandoc\pandoc-citeproc.exe" C:\Utils\Console\
+        rmdir /s /q "%TEMP%\pandoc\"
+
 ## Mac OS X
 
   - There is a package installer at pandoc's [download page].
@@ -14,6 +26,16 @@
     by downloading [this script][uninstaller]
     and running it with `perl uninstall-pandoc.pl`.
 
+  - It is possible to extract the pandoc and pandoc-citeproc
+    executables from the osx pkg file, if you'd rather not run
+    the installer.  To do this (for the version 1.19.1 package):
+
+        mkdir pandoc-extract
+        cd pandoc-extract
+        xar -x ../pandoc-1.19.1-osx.pkg
+        cat pandoc.pkg/Payload | gunzip -dc | cpio -i
+        # executables are now in ./usr/bin/, man pages in ./usr/share/man
+
   - You can also install pandoc using
     [homebrew](http://brew.sh): `brew install pandoc`.