remove  translations for unsupported languages

At the moment we are a relatively small community. We don't speak most
languages, which where supported previously. This resulted in a lot of
differences in quality and quantity of our translations.

We happily add languages again, if we find a maintainer for that
language.
Fixes waiting for Ajax in Cucumber:

* old implementation did not actually wait,
  but just checked once whether jQuery or Prototype provided
  any signs of ajaxy activity. It did not actually do anything
  with this information.
* the new implementation waits (busily!) 'til PT and jQuery
  have no signs of ajax anymore. If that takes to long,
  it'll raise Timeout::Error.
Merge branch 'feature/rails3' into feature/rails3_drop_translations_we_cannot_support_at_the_moment
fixes failing cuces
ensures cleaning up User.current after each step

When User.current is set by a spec, an instance variable of the class
gets set to the provided value. This instance variable is not reset
between specs to the next spec will "profit" as well.

This commit implements cleaning up after such lazy specs.

The lazy specs should be improved so that this cleanup is no longer
required. However I do not have the time to do this right now. As a
reminder I implemented a very verbose warning which should give us
enough of an encouragement that we will improve the specs eventually.
removes setting User.current in spec
Removes debugger statement introduced in c1bfd520
Merge pull request #187 from opf/fix/debugger_statement

Removes debugger statement introduced in c1bfd520
Improve password complexity requirements

Add a new Passwords module, which evaluates and generates passwords.
Adapt User to use this module.

In addition to checking the length, the module verifies that a password
contains a certain number of character classes like uppercase/lowercase.
These classes can be configured in the authentication settings.

Also increase the default minimum password length from 4 to 10.
Improve password complexity cukes, add copyright
Cukes: Fix another default login password
less verbose warnings, especially on the second run
updated version to 3.0.0pre3
Merge pull request #170 from opf/feature/rails3_improve_password_complexity

Improve password complexity requirements
Update CHANGELOG.rdoc
Merge pull request #145 from opf/fix/rails3-cucumber-wait-for-ajax

merged anyhow. Maybe we want to add a sleep later but it is definitly not necessary.
remove vendored select2 in favor of select2-rails gem
removes unused require
Merge pull request #184 from opf/feature/user_current_laziness_warning

Specs: user current laziness warning
only use select2 which is not greater than 3.3.2