Improve required testhelp.rb path.

[junaruga]

Last time I sent pull-request to change testhelp.rb path, and it was merged. (73bf56c).
I think it might be my mistake.

Because it looks usual to set "lib" and "test" as a ruby path than "lib" and ".".

Though it may be small thing.

For example, below Rake TestTask is using both "lib" and "test" below page.
http://rake.rubyforge.org/classes/Rake/TestTask.html
t.libs << "test"

Maybe hoe that is used in our Rakefile, its test way is kind of special, because of "lib:bin:test:.". "." is set as a Ruby load path.

bundle exec rake test
...
/usr/local/ruby-2.3.1/bin/ruby -w -Ilib:bin:test:. -e 'require "rubygems"; require "minitest/autorun"; require "test/test_thread_pool.rb"; require "test/test_puma_server.rb"; require "test/test_app_status.rb"; require "test/test_rack_server.rb"; require "test/test_minissl.rb"; require "test/test_tcp_logger.rb"; require "test/test_unix_socket.rb"; require "test/test_tcp_rack.rb"; require "test/test_null_io.rb"; require "test/test_http10.rb"; require "test/test_rack_handler.rb"; require "test/test_persistent.rb"; require "test/test_ws.rb"; require "test/test_puma_server_ssl.rb"; require "test/test_config.rb"; require "test/test_iobuffer.rb"; require "test/test_integration.rb"; require "test/test_cli.rb"; require "test/test_http11.rb"' --

I think that Including "." causes a duplicated path situation.
I am asking hoe community for this point now. (seattlerb/hoe#74)

So, this pull-request's modification looks better than before right now.

Below tests are passed.

$ bundle exec ruby -Ilib:test \
  -r 'rubygems' \
  -r 'minitest/autorun' \
  -e 'Dir.glob "./test/**/test_*.rb", &method(:require)' \
  -- -v
$ bundle exec rake test
$ bundle exec rake test:integration

How do you think?

Thank you.

[evanphx]

Ok, that makes sense as requiring relative to the top-level dir, when it's not a normal ruby dir, is a little weird.