Add overcommit gem for git hooks (rubocop)

.overcommit.yml

@@ -0,0 +1,5 @@
+PreCommit:
+  RuboCop:
+    enabled: true
+    on_warn: fail
+    problem_on_unmodified_line: ignore

Gemfile

@@ -109,6 +109,7 @@ group :development, :test do
   gem 'byebug'
   gem 'factory_bot_rails'
   gem 'listen', '~> 3.0'
+  gem 'overcommit'
   gem 'pry'
   gem 'pry-byebug'
   gem 'pry-rails'

Gemfile.lock

@@ -156,6 +156,8 @@ GEM
       mail
     case_transform (0.2)
       activesupport
+    childprocess (0.9.0)
+      ffi (~> 1.0, >= 1.0.11)
     climate_control (0.2.0)
     cliver (0.3.2)
     coderay (1.1.2)
@@ -241,6 +243,7 @@ GEM
       concurrent-ruby (~> 1.0)
     i18n-js (3.0.3)
       i18n (~> 0.6, >= 0.6.6)
+    iniparse (1.4.4)
     jaro_winkler (1.5.1)
     jbuilder (2.7.0)
       activesupport (>= 4.2.0)
@@ -330,6 +333,9 @@ GEM
       oauth2 (~> 1.1)
       omniauth (~> 1.2)
     orm_adapter (0.5.0)
+    overcommit (0.46.0)
+      childprocess (~> 0.6, >= 0.6.3)
+      iniparse (~> 1.4)
     paperclip (5.3.0)
       activemodel (>= 4.2.0)
       activesupport (>= 4.2.0)
@@ -590,6 +596,7 @@ DEPENDENCIES
   nokogiri (~> 1.8.1)
   omniauth
   omniauth-linkedin-oauth2
+  overcommit
   paperclip (~> 5.3)
   pg (~> 0.18)
   phantomjs
@@ -637,4 +644,4 @@ RUBY VERSION
    ruby 2.4.4p296
 
 BUNDLED WITH
-   1.16.6
+   1.17.1