Add 'jekyll' gem and 'bundle install'

.gitignore

@@ -33,6 +33,8 @@ config/master.key
 ## Environment normalization:
 /.bundle
 /vendor/bundle
+/.gem
+/.cache
 
 # these should all be checked in to normalize the environment:
 # Gemfile.lock, .ruby-version, .ruby-gemset
@@ -48,8 +50,10 @@ bower.json
 # Ignore pow environment settings
 .powenv
 
-# Ignore Byebug command history file.
+# Ignore command history files.
 .byebug_history
+.lesshst
+.viminfo
 
 # Ignore node_modules
 node_modules/
@@ -68,4 +72,3 @@ yarn-debug.log*
 /storage/*
 !/storage/.keep
 /public/uploads
-