NXD: get mimemagic from github

mimemagic was yanked from rubygems, so this cause gitlab to fail building. To
make it possible to keep installing this old version of gitlab we get mimemagic
from git.

Gemfile

@@ -212,6 +212,7 @@ gem 'jira-ruby', '~> 1.4'
 
 # Flowdock integration
 gem 'flowdock', '~> 0.7'
+gem "mimemagic", git: "https://github.com/mimemagicrb/mimemagic"
 
 # Slack integration
 gem 'slack-notifier', '~> 1.5.1'
@@ -247,9 +248,6 @@ gem 'ace-rails-ap', '~> 4.1.0'
 # Detect and convert string character encoding
 gem 'charlock_holmes', '~> 0.7.5'
 
-# Detect mime content type from content
-gem 'mimemagic', '~> 0.3.2'
-
 # Faster blank
 gem 'fast_blank'
 

Gemfile.lock

+GIT
+  remote: https://github.com/mimemagicrb/mimemagic
+  revision: 3543363026121ee28d98dfce4cb6366980c055ee
+  specs:
+    mimemagic (0.3.2)
+
 GEM
   remote: https://rubygems.org/
   specs:
@@ -1061,6 +1067,7 @@ DEPENDENCIES
   foreman (~> 0.84.0)
   fugit (~> 1.1)
   fuubar (~> 2.2.0)
+  mimemagic!
   gemojione (~> 3.3)
   gettext (~> 3.2.2)
   gettext_i18n_rails (~> 1.8.0)
@@ -1109,7 +1116,6 @@ DEPENDENCIES
   loofah (~> 2.2)
   mail_room (~> 0.9.1)
   method_source (~> 0.8)
-  mimemagic (~> 0.3.2)
   mini_magick
   minitest (~> 5.11.0)
   mysql2 (~> 0.4.10)