Remove unused gem whenever

Gemfile

@@ -118,8 +118,6 @@ gem 'immigrant'
 gem 'roo' # read spreadsheets
 gem 'spreadsheet_architect' # write spreadsheets
 
-gem 'whenever', require: false
-
 gem 'coffee-rails', '~> 5.0.0'
 
 gem 'angular_rails_csrf'

Gemfile.lock

@@ -245,7 +245,6 @@ GEM
     cgi (0.5.1)
     childprocess (5.0.0)
     choice (0.2.0)
-    chronic (0.10.2)
     coderay (1.1.3)
     coffee-rails (5.0.0)
       coffee-script (>= 2.2.0)
@@ -968,8 +967,6 @@ GEM
       base64
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.5)
-    whenever (1.1.2)
-      chronic (>= 0.6.3)
     xml-simple (1.1.8)
     xpath (3.2.0)
       nokogiri (~> 1.8)
@@ -1127,7 +1124,6 @@ DEPENDENCIES
   web!
   web-console
   webmock
-  whenever
   wicked_pdf!
   wkhtmltopdf-binary!