.gemspec should work with gem build

[cole-christensen]

Using

#Gemfile snippet
gem 'sassc', :git => 'git://github.com/hcatlin/sassruby.git'

and doing bundle install results in the following

---

Using sassc (0.1) from git://github.com/hcatlin/sassruby.git (at master)
sassc at /Users/chaos/.rvm/gems/ruby-2.0.0-p353@sinatra-base/bundler/gems/sassruby-bf5d8cf236b1 did not have a valid gemspec.
This prevents bundler from installing bins or native extensions, but that may not affect its functionality.
If you need to use this package without installing it from a gem repository, please contact ["hcatlin@gmail.com"] and ask them to modify their .gemspec so it can work with gem build.
The validation message from Rubygems was:
["ext/libsass/extconf.rb"] are not files

[fengb]

You need to tell bundler to explicitly include submodules:
gem 'sassc', :git => 'git://github.com/hcatlin/sassruby.git', :submodules => true