Update docs

cmd/quiver_to_markdown/README.md

@@ -2,12 +2,46 @@
 
 Converts a [Quiver] library to a set of markdown files.
 
+#### Rationale
+
+While I enjoy using [Quiver] a lot to take all sort of programming notes, I faced two issues with the original tool:
+
+- Dropbox/iCloud save don't offer the fine-grained versioning git provides
+- it is not so easy to "share" notes with collaborators
+
+This tool allows me to convert my notes to a set of Markdown files and save them on Github.
+This way I can have a fine-grained history of my changes, and a format that easy to share
+and is visible on the web.
+
 ### Installing
 
 ```sh
 $ go get -u github.com/ushu/quiver/cmd/quiver_to_markdown
 ```
 
+#### `go` dependency
+
+You need a working install of `go` to use this package.
+Provided you are on a Mac (since [Quiver] is a Mac app 😁), the simplest way to install `go`
+is probably to use [Homebrew]:
+
+```sh
+$ brew install go
+```
+
+**Note**: you might want to add the `$GOPATH/bin` to your shell `PATH`,
+(in `.profile` or equivalent) to have it available as a shell command, something like
+
+```sh
+# set GOPATH to whatever you feel like
+export GOPATH="$HOME"
+# go binalries will end up in $GOPATH/bin, so we update the path
+export PATH="$PATH:$GOPATH/bin"
+```
+
+(see the [go docs](https://golang.org/doc/code.html#GOPATH) for more details)
+
+
 ### Usage
 
 ```sh
@@ -18,14 +52,17 @@ $ quiver_to_markdown /path/to/Quiver.qvlibrary /output/path
 $ quiver_to_markdown -v
 ```
 
-Then all the notes are availation in `/output/path` as Markdown files.
+Then all the notes are available in `/output/path` as Markdown files.
 
 ## License
 
 This project is licensed under the MIT License - see the [LICENSE](../../LICENSE) file for details
 
 ## TODO
 
-* [ ] Add support for note links
+* [x] Add support for note links
+* [ ] Allow to convert back saved notes to [Quiver]
 
 [Quiver]: https://itunes.apple.com/app/id866773894
+[Homebrew]: https://brew.io
+