Update to Ruby 2.4.2

.ruby-version

@@ -1 +1 @@
-2.4.1
+2.4.2

.travis.yml

@@ -13,6 +13,7 @@ rvm:
   - 2.3.2
   - 2.3.3
   - 2.4.1
+  - 2.4.2
 before_install:
   - "env"
   - "echo 'gem: --no-ri --no-rdoc' > ~/.gemrc"

README.md

@@ -137,7 +137,7 @@ Published on https://hub.docker.com/r/wpscanteam/wpscan/
 
 ## Prerequisites
 
-- Ruby >= 2.1.9 - Recommended: 2.4.1
+- Ruby >= 2.1.9 - Recommended: 2.4.2
 - Curl >= 7.21  - Recommended: latest - FYI the 7.29 has a segfault
 - RubyGems      - Recommended: latest
 - Git
@@ -174,8 +174,8 @@ https://rvm.io/integration/gnome-terminal#integrating-rvm-with-gnome-terminal
     curl -sSL https://get.rvm.io | bash -s stable
     source ~/.rvm/scripts/rvm
     echo "source ~/.rvm/scripts/rvm" >> ~/.bashrc
-    rvm install 2.4.1
-    rvm use 2.4.1 --default
+    rvm install 2.4.2
+    rvm use 2.4.2 --default
     echo "gem: --no-ri --no-rdoc" > ~/.gemrc
     git clone https://github.com/wpscanteam/wpscan.git
     cd wpscan