message: Fix common section "Stable channels" and references to it.
diff: @@ -17,7 +17,7 @@ us on [Hyperledger's Rocket.Chat](https://chat.hyperledger.org/) at #indy-sdk to
  ## How to install
  ### Release channels
  -There are three stable channels:
  +Indy SDK release process defines the following release channels:
  * `master` - development builds for each push to master branch.
  * `rc` - release candidates.
  @@ -32,7 +32,8 @@ It is recommended to install packages with APT:
  sudo apt-get update
  sudo apt-get install -y libindy
  -See section "Release channels" for more details about {release channel}.
  +{release channel} must be replaced with master, rc or stable to define corresponded release channel.
  +See section "Release channels" for more details.
  ### Install for Windows
  @@ -59,7 +60,8 @@ that may be need for your applications.
  `You must add to PATH environment variable path to lib`. It's necessary for dynamic linkage
  your application with libindy.
  -See section "Release channels" for more details about {release channel}.
  +{release channel} must be replaced with master, rc or stable to define corresponded release channel.
  +See section "Release channels" for more details.
  ### Install for iOS
  See [wrapper iOS install documentation](wrappers/ios/README.md "How to install").
  