Add gemspec

ruby-static-checker.gemspec

@@ -0,0 +1,24 @@
+Gem::Specification.new do |s|
+  s.name        = 'ruby-static-checker'
+  s.version     = '0.0.1'
+  s.authors     = ["Greg Brockman"]
+  s.email       = ["gdb@gregbrockman.com"]
+  s.homepage    = 'https://github.com/gdb/ruby-static-checker'
+  s.summary     = %q{A static checker for Ruby}
+  s.description = %q{Ruby-static-checker is, well, a static analysis tool for
+Ruby. Ruby-static-checker's goal is to provide a simple set of sanity
+checks (starting with name error detection) for existing codebases
+without requiring any additional programmer work. This means you
+should be able to, without modifying your application, run
+
+ruby-static-checker /path/to/mainfile.rb
+
+And have the static analysis Just Work.}
+
+  s.rubyforge_project = "ruby-static-checker"
+
+  s.files         = `git ls-files`.split("\n")
+  s.executables   = `git ls-files -- bin/*`.split("\n").map{ |f| File.basename(f) }
+
+  s.add_runtime_dependency 'ParseTree'
+end