Remove indentation for github_flavored_markdown. (#1277)

Mention that github_flavored_markdown uses blackfriday,
since it's no longer indented under it.

Also make indentation consistent (4 spaces) for another
indented line.

README.md

@@ -855,7 +855,7 @@ See [go-hardware](https://github.com/rakyll/go-hardware) for a comprehensive lis
 * [asn1](https://github.com/PromonLogicalis/asn1) - Asn.1 BER and DER encoding library for golang
 * [colfer](https://github.com/pascaldekloe/colfer) - Code generation for the Colfer binary format
 * [go-capnproto](https://github.com/glycerine/go-capnproto) - Cap'n Proto library and parser for go
-  * [bambam](https://github.com/glycerine/bambam) - generator for Cap'n Proto schemas from go.
+    * [bambam](https://github.com/glycerine/bambam) - generator for Cap'n Proto schemas from go.
 * [go-codec](https://github.com/ugorji/go) - High Performance, feature-Rich, idiomatic encode, decode and rpc library for msgpack, cbor and json, with runtime-based OR code-generation support
 * [gogoprotobuf](https://github.com/gogo/protobuf) - Protocol Buffers for Go with Gadgets
 * [goprotobuf](https://github.com/golang/protobuf) - Go support, in the form of a library and protocol compiler plugin, for Google's protocol buffers.
@@ -951,11 +951,11 @@ See [go-hardware](https://github.com/rakyll/go-hardware) for a comprehensive lis
     * [allot](https://github.com/sbstjn/allot) - Placeholder and wildcard text parsing for CLI tools and bots
     * [bbConvert](https://github.com/CalebQ42/bbConvert) - Converts bbCode to HTML that allows you to add support for custom bbCode tags
     * [blackfriday](https://github.com/russross/blackfriday) - Markdown processor in Go
-        * [github_flavored_markdown](https://godoc.org/github.com/shurcooL/github_flavored_markdown) - GitHub Flavored Markdown renderer with fenced code block highlighting, clickable header anchor links.
     * [bluemonday](https://github.com/microcosm-cc/bluemonday) - HTML Sanitizer
     * [editorconfig-core-go](https://github.com/editorconfig/editorconfig-core-go) - Editorconfig file parser and manipulator for Go
     * [enca](https://github.com/endeveit/enca) - Minimal cgo bindings for [libenca](http://cihar.com/software/enca/).
     * [genex](https://github.com/alixaxel/genex) - Count and expand Regular Expressions into all matching Strings
+    * [github_flavored_markdown](https://godoc.org/github.com/shurcooL/github_flavored_markdown) - GitHub Flavored Markdown renderer (using blackfriday) with fenced code block highlighting, clickable header anchor links.
     * [go-humanize](https://github.com/dustin/go-humanize) - Formatters for time, numbers, and memory size to human readable format.
     * [go-nmea](https://github.com/adrianmo/go-nmea) - NMEA parser library for the Go language.
     * [go-pkg-rss](https://github.com/jteeuwen/go-pkg-rss) - This package reads RSS and Atom feeds and provides a caching mechanism that adheres to the feed specs.