update README

README.markdown

@@ -0,0 +1,61 @@
+# Ruby Readability
+
+Command line:
+
+    (sudo) gem install ruby-readability
+
+Bundler:
+
+    gem "ruby-readability", :require => 'readability'
+
+## Example
+
+    require 'rubygems'
+    require 'readability'
+    require 'open-uri'
+
+    source = open('http://lab.arc90.com/experiments/readability/').read
+    puts Readability::Document.new(source).content
+
+## Options
+
+You may provide options to Readability::Document.new, including:
+
+    :tags                - the base whitelist of tags to sanitize, defaults to `%w[div p]`
+    :remove_empty_nodes  - remove `<p>` tags that have no text content; also removes p tags that contain only images
+    :attributes          - whitelist of allowed attributes
+    :debug               - provide debugging output, defaults `false`
+    :encoding            - if the page is of a known encoding, you can specify it; if left unspecified,
+                           the encoding will be guessed (only in Ruby 1.9.x)
+    :html_headers        - in Ruby 1.9.x these will be passed to the `guess_html_encoding` gem 
+                           to aid with guessing the HTML encoding
+    :ignore_image_format - for use with `.images`.  For example: `:ignore_image_format => ["gif", "png"]`
+    :min_image_height    - set a minimum image height for `.images`
+    :min_image_width     - set a minimum image width for `.images`
+
+## Command Line Tool
+
+Readability comes with a command-line tool for experimentation in bin/readability.
+
+    Usage: readability [options] URL
+        -d, --debug                      Show debug output
+        -i, --images                     Keep images and links
+        -h, --help                       Show this message
+
+## Images
+
+You can get a list of images in the content area with `.images`.  This feature requires that the `mini_magick` gem be installed.
+
+    p Readability::Document.new(source).images
+
+## Potential Issues
+
+* If you're on a Mac and are getting segmentation faults, see the discussion at https://github.com/tenderlove/nokogiri/issues/404 and consider updating your version of libxml2.  Version 2.7.8 of libxml2 with the following worked for me:
+
+    gem install nokogiri -- --with-xml2-include=/usr/local/Cellar/libxml2/2.7.8/include/libxml2 --with-xml2-lib=/usr/local/Cellar/libxml2/2.7.8/lib --with-xslt-dir=/usr/local/Cellar/libxslt/1.1.26
+
+# License
+
+This code is under the Apache License 2.0.  http://www.apache.org/licenses/LICENSE-2.0
+
+Ruby port by starrhorne, libc, and iterationlabs.  Special thanks to fizx and marcosinger.