TimeWithZone#advance: leverage Hash#values_at and non-block form of #any? for a little less line noise, and a slight speedup (thanks raggi and Roman2K)

Signed-off-by: NPratik Naik <pratiknaik@gmail.com>

Add thorough tests for Time-object #past?, #future? and #today. Fix TimeWithZone #today? to use #time instead of #utc for date comparison. Update changelog. [#720 state:resolved]

Introduce convenience methods past?, today? and future? for Date and Time classes to facilitate Date/Time comparisons.

Get rid of 'Object#send!'. It was originally added because it's in Ruby 1.9, but it has since been removed from 1.9.
Signed-off-by: NJeremy Kemper <jeremy@bitsweat.net>

Conflicts:

	actionpack/test/controller/layout_test.rb

Fix TimeWithZone unmarshaling: coerce unmarshaled Time instances to utc, because Ruby's marshaling of Time instances doesn't respect the zone

TimeWithZone: when crossing DST boundary, treat Durations of days, months or years as variable-length, and all other values as absolute length. A time + 24.hours will advance exactly 24 hours, but a time + 1.day will advance 23-25 hours, depending on the day. Ensure consistent behavior across all advancing methods.

Signed-off-by: NPratik Naik <pratiknaik@gmail.com>

TimeWithZone: date part getter methods (#year #mon #day etc) are defined on class; no longer relying on method_missing

Signed-off-by: NPratik Naik <pratiknaik@gmail.com>

TimeWithZone#method_missing: send to utc to advance with dst correctness, otherwise send to time. Adding tests for time calculations methods

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@9208 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

Bundling abbreviated version of TZInfo gem 0.3.8: only the classes and zone definitions required to support Rails time zone features are included. If a recent version of the full TZInfo gem is installed, this will take precedence over the bundled version

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@9149 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@9108 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

TimeWithZone time conversions don't need to be wrapped in TimeOrDateTime, because TZInfo does this internally

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@9106 5ecf4fe2-1ee6-0310-87b1-e25e094e27de