Clean up the nimpretty code

doc/ale-nim.txt

@@ -21,5 +21,25 @@ g:nim_nimlsp_nim_sources                             *g:nim_nimlsp_nim_sources*
   command.
 
 
+===============================================================================
+nimpretty                                                   *ale-nim-nimpretty*
+
+
+g:ale_nim_nimpretty_executable                 *g:ale_nim_nimpretty_executable*
+                                               *b:ale_nim_nimpretty_executable*
+  Type: |String|
+  Default: `'nimpretty'`
+
+  This variable can be changed to use a different executable for nimpretty.
+
+
+g:ale_nim_nimpretty_options                       *g:ale_nim_nimpretty_options*
+                                                  *b:ale_nim_nimpretty_options*
+  Type: |String|
+  Default: `'--maxLineLen:80'`
+
+  This variable can be changed to modify flags given to nimpretty.
+
+
 ===============================================================================
   vim:tw=78:ts=2:sts=2:sw=2:ft=help:norl:

doc/ale-supported-languages-and-tools.txt

@@ -284,6 +284,7 @@ Notes:
 * Nim
   * `nim check`!!
   * `nimlsp`
+  * `nimpretty`
 * nix
   * `nix-instantiate`
   * `nixpkgs-fmt`

doc/ale.txt

@@ -2361,6 +2361,7 @@ documented in additional help files.
   nim.....................................|ale-nim-options|
     nimcheck..............................|ale-nim-nimcheck|
     nimlsp................................|ale-nim-nimlsp|
+    nimpretty.............................|ale-nim-nimpretty|
   nix.....................................|ale-nix-options|
     nixpkgs-fmt...........................|ale-nix-nixpkgs-fmt|
   nroff...................................|ale-nroff-options|