Routes

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* Split up the Routes docs.
* Fix bug with relative URL's using qualified merging host and URL without
including the appropriate slash. Fixes 13.
* Fix bug with mapper.extend and Routes modifying their original args.
Fixes 24.
* Fix url.current() not returning current args when explicit is True.
* Added explicit way to directly use the Mapper to match with environ.
* Fix bug with improper len placement for submapper.
* Adding regular expression builder for entire regexp for faster rejection
in a single regexp match should none of the routes match.
* Give Mapper a tabular string representation.
* Make SubMapper objects nestable and add route-generation helpers.
* Add SubMapper-based collections.
* Make the deprecated Mapper.minimization False (disabled) by default.
* Make the mapper explicit (true) by default.

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* Extensive documentation rewrite.
* Added Mapper.extend function that allows one to add lists of Routes objects
to the mapper in one batch, optionally with a path_prefix.
* Added Mapper.submapper function that returns a SubMapper object to enable
easier declaration of routes that have multiple keyword argument options
in common.
* Mapper controller_scan argument now handles None, and lists of controller
names in addition to a callable.
* Route object now takes a name parameter, which is the name it responds to.
This name is automatically added when called by using Mapper's connect
class method.
* Added optional LRU object for use with Routes when URL's change too often
for the Routes urlcache dict to be a viable option.

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* Tweak to use WebOb Request rather than Paste.
* Performance tweaks for URL recognition.
* Bugfix for routes.middleware not re.escaping the path_info before moving it
to the script name.

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* Bugfix for unicode encoding problems with non-minimized Route generation.
Spotted by Wichert Akkerman.
* Bugfix for when environ is {} in unit tests.

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* Removing LRU cache due to performance and threading issues. Cache does hit
a max-size for the given routes.

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* Adding LRU cache instead of just dict for caching generated routes. This
avoids slow memory leakage over long-running and non-existent route
generation.
* Adding URLGenerator object.
* Adding redirect routes.
* Static routes can now interpolate variable parts in the path if using {}
variable part syntax.
* Added sub_domain condition option to accept False or None, to require that
there be no sub-domain provided for the route to match.