`--without rmagick` option for `bundle install` is no longer necessary (#33208).

Patch by Go MAEDA.


git-svn-id: http://svn.redmine.org/redmine/trunk@19625 e93f8b46-1217-0410-a6f0-8f06a7374b81

doc/INSTALL

@@ -33,10 +33,6 @@ Optional:
 4. Install the required gems by running:
      bundle install --without development test
 
-   If ImageMagick is not installed on your system, you should skip the
-   installation of the rmagick gem using:
-     bundle install --without development test rmagick
-
    Only the gems that are needed by the adapters you've specified in your
    database configuration file are actually installed (eg. if your
    config/database.yml uses the 'mysql2' adapter, then only the mysql2 gem