remove superfluous to_s in ERB::Util.html_escape

Re-launch assets:precompile task using (Rake.)ruby instead of Kernel.exec so it works on Windows

This reverts commit 0e4748cd.

To the app developer, this means configuration add in
config/initializers/* will not be executed.

Plugins developers need to special case their initializers that are
meant to be run in the assets group by adding :group => :assets.

Conflicts:

	railties/CHANGELOG
	railties/test/application/assets_test.rb

Remove Sprockets compute_public_path, AV compute_plubic_path can be used 

Minor doc fix to String#constantize

Sprockets to use config.assets.prefix, with tests

Added ActiveSupport::Inflector.safe_constantize and String#safe_constantize; refactored common constantize tests into ConstantizeTestCases

Allow both sym and array for details options in #render. using LC#registered_details to extract options.

ActiveModel JSON serialization bug fix

fixed a bug with the json serialization when the class setting is set to not include the root, but an instance is serialized with the root option passed as true

FileStore key_file_path does not properly limit filenames to 255 characters

For example, calling hello.erb is now deprecated. Since Rails 3.0
passing the handler had no effect whatsover. This commit simply
deprecates such cases so we can clean up the code in later releases.

it is now possible to pass details options (:formats, :details, :locales, ...) to #render, #find_template and friends. this doesn't change anything in global context.

Named routes are modifying passed options

Updated existing test that fails with this fix (8d63678d).  Before the fix the test was giving a false positive, because file_store.key_file_path would return an empty filename (i.e. test/tmp_cache/4D0/F4D rather than test/tmp_cache/4D0/F4D/xxxx…).

Even though the fix referenced above divides the filename into directories to prevent it from being too long, it seems that 1000 characters will always raise an error, so reducing the key size to 900).