* Used the Sequel::Postgres::PGArray::Parser class from
  https://github.com/jeremyevans/sequel/blob/master/lib/sequel/extensions/pg_array.rb
* The saner method to parse multi-dimensional array-strings
  is to NOT use regexps and use some sort of parser instead
* Changed String.valid_postgres_array? to use constants instead
  of variables to defined the regexps
* Converting timestamps to current Rails timezone using `in_time_zone`

Removed String.valid_postgres_array? because there is no easy way to
validate array-string using Regexps alone. One will have to parse the
string into an array to check if it's valid -- a task that the PG database
would anyways do.

Removed check in `quote_with_array`

…g to DB

…rrect

…es because the actual function in Rails 3.2.x has changed. The monkeypatched version was unable to handle serialized attributes and was causing all serializations to barf.

* Removed the method_chaing for quote_without_array, because it's not required in the new approach.
* Added ActiveRecord::Coders::PgArray to act as a serializer/de-serializer for all array columns. One has to expilicity define how to serialize a column, like:
    `serialize :tags, ActiveRecord::Coders::PgArray(:string)`

… we override the reader method