initial commit for collector implementation
bind visitor working with collector object
fixing some tests in to_sql
to_sql is passing
Merge branch 'master' into collector

* master:
  remove order_clauses since we do not use it
  fix whitespace and unsupported method args
  Add Regexp and NotRegexp nodes for PostgreSQL
  Revert "Merge pull request #253 from corrupt952/master"
  flatten object.children in visit_Arel_Node_And
  Added right and full outer joins

Conflicts:
	lib/arel/visitors/to_sql.rb
	lib/arel/visitors/visitor.rb
making some of the sql manager tests pass
Merge branch 'master' into collector

* master:
  removing unused join_sql method
more select manager tests passing
select manager tests are passing
push reduction visitors to a reduction base class

this lets our old depth first and dot visitors to work normally
fix sqlite visitor
postgresql visitor is working
oracle tests passing
fixing mysql visitor
Merge branch 'master' into collector

* master:
  build the ast rather than passing around strings
  move the ORDER BY to the RowNumber method
  move all the "ORDER BY" together
  use if / else so my brain stops hurting
  refactor mssql nodes to move away from string interpolation
loop over cores twice to make the collector implementation more convenient
Merge branch 'master' into collector

* master:
  loop over cores twice to make the collector implementation more convenient
finally stop returning strings
Merge branch 'master' into collector

* master:
  finally stop returning strings
mssql visitor is working