Update rubies in .travis.yml

Also add "test-unit" gem to gemspec in order to prevent new rubies failures

Author: ojab

.travis.yml

@@ -2,10 +2,12 @@ language: ruby
 rvm:
   - 1.9.3
   - 2.0.0
-  - 2.1.2
+  - 2.1
+  - 2.2
   # optional
+  - ruby-head
   - jruby-19mode
-  - rbx-19mode
+  - jruby-head
   - rbx-2
 
 env:
@@ -19,8 +21,9 @@ script: bundle exec rake ci
 
 matrix:
   allow_failures:
+    - rvm: ruby-head
     - rvm: jruby-19mode
-    - rvm: rbx-19mode
+    - rvm: jruby-head
     - rvm: rbx-2
   fast_finish: true
 

net-ldap.gemspec

@@ -32,4 +32,5 @@ the most recent LDAP RFCs (4510-4519, plutions of 4520-4532).}
   s.add_development_dependency("flexmock", "~> 1.3")
   s.add_development_dependency("rake", "~> 10.0")
   s.add_development_dependency("rubocop", "~> 0.28.0")
+  s.add_development_dependency("test-unit")
 end