Rename the idris-lang layer to idris

The idris-mode package has been updated to no longer use the
idris-packages variable, which allows the Idris layer to safely be
renamed to the standard for other languages.

layers/+lang/idris/README.org

@@ -24,7 +24,7 @@ This layer adds support for the [[http://www.idris-lang.org/][Idris]] language.
 To use this layer, add it to your =~/.spacemacs=
 
 #+BEGIN_SRC elisp
-(setq-default dotspacemacs-configuration-layers '(idris-lang))
+(setq-default dotspacemacs-configuration-layers '(idris))
 #+END_SRC
 
 ** Idris

layers/+lang/idris/packages.el

@@ -10,14 +10,12 @@
 ;;
 ;;; License: GPLv3
 
-;; We name this layer idris-lang instead of idris because
-;; the variable `idris-packages' is already used by `idris-mode'
-(setq idris-lang-packages '(idris-mode))
+(setq idris-packages '(idris-mode))
 
-(defun idris-lang/init-idris-mode ()
+(defun idris/init-idris-mode ()
   (use-package idris-mode
     :defer t
-    :init
+    :config
     (progn
       (defun spacemacs/idris-load-file-and-focus (&optional set-line)
         "Pass the current buffer's file to the REPL and switch to it in