doc: pants.bootstrap -> pants

    also, don't imply there's just one goal
Improve scrubbing of namespace packages

Problem: since we can't force python -S using /usr/bin/env, we can't prevent
importing site.  But 'import site' populates sys.modules with placeholder
modules containing .__path__ attributes with site-packages baked in.  This
means even if we scrub sys.path and sys.path_importer_cache, it's still
possible for __import__ to pick up things from site-packages.  This scrubs
sys.modules as well.

Reviewed at https://rbcommons.com/s/twitter/r/116/
Fix cross-device symlink bug.
Check correct config section for python-setup options

config.getdefault() will only check in the [DEFAULT] section.

Signed-off-by: John Sirois <jsirois@twitter.com>
doc: howto_contribute += ask an rbcommons admin to add your acct to the group
doc: fix build dict entries for some py things
Do not use PANTS_DEV when running tests.

See https://groups.google.com/d/topic/pants-devel/fuZ4WaAPxRk/discussion for background.

Reviewed at https://rbcommons.com/s/twitter/r/126/
De-dup sources and report this.
Correctness fix for ScroogeGen - namespace_map's were not being translated for uniform equals behavior.
doc: setup_py's with_binaries method is useful, so help doc builder detect it
Add ivy resolved classpaths as a unit.
Fix a comment typo
remove code from ivy/__init__.py into properly-named files.
Move code from command/__init__.py to a properly-named file.

In preparation for move to pantsbuild.
Move code from engine/__init__.py to a properly-named file.

In preparation for the move to pantsbuild.
Revert "Move code from engine/__init__.py to a properly-named file."

This reverts commit 1d179340d9c29b77560769bd8ce3da66dabf3ce8.
Revert "Move code from command/__init__.py to a properly-named file."

This reverts commit 6b024d7c9735f43eb80389be293183ac77a10e68.
Default the nailgun workdir sensibly.

Also kill cruft nailgun config settings in pants.ini.
doc: troubleshooting += Failed to read ng output after 5 seconds
Move code out of __init__.py files, attempt #2.

This includes getting rid of command registration magic,
since it's complicated and commands are going away entirely anyway.