Merge pull request #976 from github/urubos-patch-1

Fix misspelling

Author: urubos

docs/requirements.md

@@ -10,7 +10,7 @@ system (Ubuntu is highly recommended) with [bash][1], [git][2], [OpenSSH][3] 5.6
 
 The parallel backup and restore feature will require [GNU awk][10] and [moreutils][9] to be installed.
 
-We encourage the use of [Docker](docker.md), as it ensures compatible versions of the aforementioned software are availablt to backup-utils.
+We encourage the use of [Docker](docker.md), as it ensures compatible versions of the aforementioned software are available to backup-utils.
 
 The backup host must be able to establish outbound network connections to the
 GitHub appliance over SSH. TCP port 122 is used to backup GitHub Enterprise Server.