Allow set of driver_needs_utf8 option

Allow setting the 'driver_needs_utf8' option on django's settings.
Fix django version check in get_ordering
update README
Patch by Tojiro@gmail.com and czambran@gmail.com for issue (#99)

Allows order_by on annotated field names not in the database.

https://code.google.com/p/django-pyodbc/issues/detail?id=99
attempted to bring up to speed with 1.6 but still get error on line 195 in compiler.py `if column.endswith("AS [%s]" % alias_name):` AttributeError: "list" object has no attribute "endswith"
Allow django 1.7
Merge pull request #51 from jieter/master

Allow django 1.7
Update README.md
Solves Issue 2 from #55
Merge pull request #55 from jordanorc/master

Django 1.7 compatibilty #52
Merge pull request #49 from GotenXiao/fix-django-version-check

Fix django version check in get_ordering
bump version to 0.2.4
Rolled back unintended change on version
Merge branch 'master' of github.com:martingalloar/django-pyodbc into martingalloar-master

* 'master' of github.com:martingalloar/django-pyodbc:
  Rolled back unintended change on version
  Allow set of driver_needs_utf8 option
Merge branch 'martingalloar-master'

* martingalloar-master:
  Rolled back unintended change on version
  Allow set of driver_needs_utf8 option
First pass at fixing SQL Server 2000 pagination
Fixing SQL Server 2000 pagination
Fixing SQL Server 2000 pagination.

Fixing SQL Server 2000 pagination
Initial DB2 detection and support
add optional 3rd arg in operations.field_case_sql()

+ neither internal_type nor db_type are used anywhere in field_case_sql function
+ complies with both django 1.6 API (3 args) and Django 1.5 (2 args)
+ patch proposed by christian@bachand-tremblay.com on https://github.com/lionheart/django-pyodbc/issues/33
+ tested on Django 1.5 and 1.6 with FreeTDS and pyodbc 3.0.7 by HL on a fc16 box communicating with sqlserver 2008