Methods like status and location are interfering with redirect_to [Closes #2511]

Conflicts:
	RELEASING_RAILS.rdoc
	actionpack/lib/sprockets/railtie.rb
	actionpack/test/template/sprockets_helper_test.rb
	activerecord/test/cases/calculations_test.rb
	railties/guides/source/3_1_release_notes.textile
	railties/guides/source/active_resource_basics.textile
	railties/guides/source/command_line.textile

This reverts commit 7a4e545eccf834cb620df0f909ef3f4bec4e6608.

Two commented lines in example to match the
commit (8845ae68)

X-Sendfile headers are now set to nil and are off by default.
See commit eff7fdde

v2.8.0 of Capistrano has a recipe to handle precompile
and symlinking.

Changed << to += because we are _concatenating_
this new array to the end of config array, NOT
pushing this array in it.

Adding Basic file for ActiveModel. @vatrai and @sukeerthiadiga is going to take care other detailed stuff.