Apostrophes must be replaced by a separator instead of being simply removed

For instance :
"a cat’s toys" should give
"a-cat-s-toys"
In latin language this is really critical, for instance :
"une œuvre d’art" should give
"une-oeuvre-d-art" and never "une-oeuvre-dart" which means nothing.
Merge pull request #1422 from dimitridamasceno/1.7/develop

Apostrophes must be replaced by a separator instead of being removed
bumped the docblock version to 1.7
fixed reading the REST auth method from config
New Response::redirect_back(), to go back where you came from
make sure redirect_back() doesn't redirect to itself
make sure Agent tests can run with known test values
added previous/key lookup by key and value
fixed Arr tests, assertEquals appearently does loose comparison...
improved profiler SQL query analysis (MySQL only)
updated the Markdown library to 1.2.6
fixed small profiler css issue
Fix bug with expired session

If the session is expired the Redis driver try to set $this->keys['previous_id'] with $this->keys['session_id'] which do not exist also it try to set $this->keys['session_id']  with $payload['rotated_session_id'] but we have just set the payload variable with the retated_session from Redis.
We just need to unserialize the data like in Memcached and File driver.
add default extension if there is not one set
Fixup many hardcoded unix paths, minor coding styles (spaces around concatenation)
Merge pull request #1433 from daidais/patch-1

Fix bug with expired session
Merge pull request #1436 from AlbinoGeek/1.7/develop

Fixup hardcoded *nix paths, some spaces around concatenation
Update rest.php

Avoid PHP error if key does not exist
Merge pull request #1438 from Art4/patch-1

Avoid PHP error in rest controller
Merge pull request #1434 from propcom/bugfix-config-extension

add default extension if there is not one set