Issue #1372122 by klausi, sun, beejeebus, juampy, mradcliffe, tim.plunkett, cha0s: Fixed STOP the registry integrity constraint violation nightmare.

#797024 follow-up by justinrandell: Remove critical performance regression due to stale file time values.

#797024 by pwolanin, justinrandell: Fixed Moving a class between files can cause SQL errors on registry rebuild.

- Patch #760982 by yhager, jbrown, aspilicious, David_Rothstein: tokenizer PHP extension not required.

- Patch #661420 by justinrandell, David_Rothstein: made installation of modules much more efficient.

#561452 by pwolanin and David_Rothstein: Add API function to get module/theme info without rebuilding it.

#497118 by chx, catch, pwolanin, JoshuaRogers, and Jacob Singh: Remove the function registry. While the hope was that this would result in improved performance for low-end hosts, it comes at the expense of critical development experience problems and less benefit than something like APC. Class registry remains intact to facilitate autoloading.

Of all the patches to accidentally commit without a message. :( Rolling back registry rip. Let's try that again.

#517814 by jmstacey, justinrandell, pwolanin, drewish, Jody Lynn, aaron, dopry, and c960657: Converted File API to stream wrappers, for enhanced private/public file handling, and the ability to reference other storage mechanisms such as s3:// and flicker://.

- Patch #513592 by Damien Tournoud: make it faster to rebuild the registry, mainly to improve performance of SimpleTest.

- Patch #74645 by drewish, roychri et al: modify file_scan_directory to use a regex for the nomask (and code clean-up).

- Patch #298600 by chx, justinrandell, Damien, et al: make module_implements work regardless of bootstrap phase.

- Patch #225450 by Crell, chx, bjaspan, catch, swentel, recidive et al: next generation database layer for Drupal 7.

- Patch #287877 by dmitrig01: rename drupal_rebuild_code_registry() to registry_rebuild() for consistency.

  et al.  Can you say 'registry'?  Drupal now maintains an internal registry of
  all functions or classes in the system, allowing it to lazy-load code files as
  needed (reducing the amount of code that must be parsed on each request). The
  list of included files is cached per menu callback for subsequent loading by
  the menu router. This way, a given page request will have all the code it needs
  but little else, minimizing time spent parsing unneeded code.