an interpreter variant that supports all interpreter flags (AFAIK).  this commit contains core implementation (in easy_install module) and tests of all functionality except import_sitecustomize.  Integration into zc.recipe.egg and tests for import_sitecustomize (which will be more involved, and in tests.py) will follow.

this exposes the ability to request that site be imported in the ``script`` function. A later commit will expose this in the buildout configuration choices.

eliminate trailing spaces and normalize initial spacing of examples (some had five spaces, and the usual is four).

normalize text indentation, favoring not indenting expository text.  fix a few typos and spacing problems.

remove some superfluous whitespace, capitalize a comment, and normalize option error message to look like the ones in zc.buildout.

make a branch for the minor cleanup in gary-support-system-python branches.  this will be the base branch for my effort to break up the gary-support-system-python branch into five.

Revert to old style path.

- Incrementing didn't work properly when extending multiple files.
  https://bugs.launchpad.net/zc.buildout/+bug/421022

windows, urllib raises an invalid ioerror.

windows, urllib raises an invalid ioerror.

  The standard Python -m option didn't work for custom interpreters.

  Scripts run using generated interpreters didn't have __file__ set correctly.

  Scripts generated with relative-paths eanbled couldn't be
  symbolocally linked to other locations and still work.

  Option incrementing and decrementing didn't work for options
  specified on the command line.