an alternative in $: so that Kernel.#require does not load
more rubygems.rb.
Resolves many failures in test/rubygems/*.
* gem_prelude.rb (Gem.load_full_rubygems_library): supports case
the rubygems to load is not in $(rubylibprefix).
(Gem.path_to_full_rubygems_library): new method for the changes in
purelib.rb and Gem.load_full_rubygems_library.
(Gem.fake_rubygems_as_loaded): new method.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@24117 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
load path to get rid of load pre-installed extensions/libraries.
[ruby-core:11017]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@12333 b2dd03c8-39d4-4d8f-98ff-823fe69b080e