checks if docs dir exists

Rakefile

@@ -37,7 +37,7 @@ end
 
 # Updates GITHUB PAGES
 desc 'Update gh-pages branch'
-task 'docs:pages' => ['docs/.git', :docs] do
+task 'docs:pages' => ['docs/', 'docs/.git', :docs] do
   rev = `git rev-parse --short HEAD`.strip
   Dir.chdir 'docs' do
     last_commit = `git log -n1 --pretty=oneline`.strip
@@ -60,6 +60,10 @@ task 'docs:pages' => ['docs/.git', :docs] do
   end
 end
 
+file 'docs/' do |f|
+  Dir.mkdir(f.name) if !File.exists?(f.name)
+end
+
 # Update the pages/ directory clone
 file 'docs/.git' => ['docs/', '.git/refs/heads/gh-pages'] do |f|
     sh "cd docs && git init -q && git remote add origin git@github.com:spire-io/spire.io.rb.git" if !File.exist?(f.name)