Add .rspec to gem files, to make Travis happy

Author: zverok

.travis.yml

@@ -59,7 +59,7 @@ script:
   # Test ruby gem
   - gem install gem-path --no-ri --no-rdoc
   - cd $HOME/gems/symengine-0.1.0/
-  - bundle exec rspec --require ./spec/spec_helper.rb
+  - bundle exec rspec
 
 notifications:
   email: false

symengine.gemspec

@@ -7,7 +7,7 @@ Gem::Specification.new do |gem|
     gem.email = ["abinashdakshana999@gmail.com"]
     gem.homepage = 'https://github.com/sympy/symengine'
     gem.files = Dir["lib/**/*", "bin/*", "LICENSE", "*.md", "ext/**/*", "spec/**/*", "CMakeLists.txt", "Gemfile",
-                    "cmake/FindRuby.cmake", "symengine.gemspec"]
+                    "cmake/FindRuby.cmake", "symengine.gemspec", ".rspec"]
     gem.require_paths = ["lib"]
     gem.extensions = ["ext/symengine/extconf.rb"]
     gem.license = 'MIT'