Fix after boot thread-safety issue

Demo to reproduce: https://gist.github.com/etehtsea/9143028

Example stacktrace:

```
[INFO ] TorqBox::Server  - TorqBox 0.1.7 starting...
[INFO ] org.projectodd.wunderboss.web.WebComponent  - Undertow listening on localhost:8080
[INFO ] org.projectodd.wunderboss.web.WebComponent  - Started web context /
[ERROR] io.undertow.request  - Blocking request failed HttpServerExchange{ GET /}
org.jruby.exceptions.RaiseException: (NameError) method "OPTIONS   /" already exists and cannot be used as an unbound method name
	at RUBY.generate_api_method(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/endpoint.rb:26)
	at RUBY.initialize(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/endpoint.rb:50)
	at RUBY.route(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:353)
	at RUBY.options(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:396)
	at RUBY.add_head_not_allowed_methods_and_options_methods(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:578)
	at org.jruby.RubyHash.each(org/jruby/RubyHash.java:1338)
	at RUBY.add_head_not_allowed_methods_and_options_methods(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:572)
	at RUBY.initialize(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:527)
	at RUBY.compile(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:29)
	at RUBY.call(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:37)
	at RUBY.call(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/gems/rack-1.5.2/lib/rack/commonlogger.rb:33)
[ERROR] io.undertow.request  - Blocking request failed HttpServerExchange{ GET /}
org.jruby.exceptions.RaiseException: (NameError) method "   /" already exists and cannot be used as an unbound method name
	at RUBY.generate_api_method(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/endpoint.rb:26)
	at RUBY.initialize(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/endpoint.rb:50)
	at RUBY.route(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:353)
	at RUBY.add_head_not_allowed_methods_and_options_methods(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:586)
	at org.jruby.RubyHash.each(org/jruby/RubyHash.java:1338)
	at RUBY.add_head_not_allowed_methods_and_options_methods(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:572)
	at RUBY.initialize(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:527)
	at RUBY.compile(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:29)
	at RUBY.call(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:37)
	at RUBY.call(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/gems/rack-1.5.2/lib/rack/commonlogger.rb:33)
[ERROR] io.undertow.request  - Blocking request failed HttpServerExchange{ GET /}
org.jruby.exceptions.RaiseException: (NameError) method 'PUT POST DELETE PATCH   /' not defined in Grape::Endpoint
	at org.jruby.RubyModule.remove_method(org/jruby/RubyModule.java:2344)
	at RUBY.generate_api_method(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/endpoint.rb:30)
	at RUBY.initialize(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/endpoint.rb:50)
	at RUBY.route(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:353)
	at RUBY.add_head_not_allowed_methods_and_options_methods(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:586)
	at org.jruby.RubyHash.each(org/jruby/RubyHash.java:1338)
	at RUBY.add_head_not_allowed_methods_and_options_methods(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:572)
	at RUBY.initialize(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:527)
	at RUBY.compile(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:29)
	at RUBY.call(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/bundler/gems/grape-466579209276/lib/grape/api.rb:37)
	at RUBY.call(/Users/kes/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/gems/rack-1.5.2/lib/rack/commonlogger.rb:33)
127.0.0.1 - - [22/Feb/2014 00:43:26] "GET / " 200 5 2.7050
127.0.0.1 - - [22/Feb/2014 00:43:26] "GET / " 200 5 2.8660
127.0.0.1 - - [22/Feb/2014 00:43:26] "GET / " 200 5 2.8530
127.0.0.1 - - [22/Feb/2014 00:43:26] "GET / " 200 5 2.8620
127.0.0.1 - - [22/Feb/2014 00:43:26] "GET / " 200 5 2.8560
127.0.0.1 - - [22/Feb/2014 00:43:26] "GET / " 200 5 2.8740
```