Stores the Setting.maximum(:updated_on) in a thread-local-variable

this gets rid of numerous redundant db-calls to check with every call to
a setting, if the settings have been updated. Checking this one and one
time only for a request should be sufficient.

let's see, if this works for the admin-specs to update settings.
Added the request-store, to make sure that thread-local variables are cleaned up after the request
replaced the pulled code with proper gem-reference

The railtie now automatically makes sure, that the middleware is used,
and the included gem better respects the copyright of the used solution.
forgot the removal of the middleware&the comment in application.rb
Changelog.
Merge pull request #490 from opf/fix/redundant_settings_max_updated_on

add a request-store and put the settings_max_updated_on into the request to avoid redundant calls
Fixes changelog.

Those issues wrongfully ended up in pre20.
Merge pull request #496 from opf/fix/changelog

Fixes changelog.
Allows flash message arrays
Sets standard type if no type is selected
Adds bug fix changelog entry

[skip ci]
Handles unselect of types still referenced
Adds type settings specs
Fixes postgres issue
Merge pull request #493 from opf/feature/rails3_project_settings_types_tab

[FEATURE] Handle empty type selection
Changelog.

Adds tickets that somehow didn't make it into the changelog w/ their
code.
Merge pull request #497 from opf/fix/changelog

Changelog.
Merge remote-tracking branch 'opf/feature/rails3' into feature/planning_comparison

Conflicts:
	doc/CHANGELOG.md