RELEASE 2.9.1: PR #364: don't let packages pollute namespace of future packages

Merges PR: #364

PLEASE NOTE: There is an outside chance that existing packages might be inadvertently relying on the current buggy behavior. I don't think this is likely, but I'm pointing it out here in case you see odd behavior when updating to this version.

RELEASE 2.9.0: Misc Small PRs

Adds:

hg: print log from most recent to oldest, so don't truncate current commit
#356

even if there are no memcached servers, DoNotCache results are unwrapped
#361

minor fixes (test_solver)
#370

fix for TestRelease.test_2_variant_add
#371

invalidate memcache if a package file has been deleted / moved / etc
#376

add max_package_changelog_revisions config option
#357

allow configuration of truncate cap for shell error output
#363

added option to force color output, even if not a tty
#365

RELEASE 2.8.0: Custom build commands

Packages can now provide their own build commands in their package.py:

# in package.py
build_command = "make -f {root}/Makefile {install}"

See:
https://github.com/nerdvegas/rez/wiki/Building-Packages#custom-build-commands

RELEASE 2.7.0: rez-test tool

Packages can now define their own tests in their package.py, and an accompanying 'rez-test' tool will list and run these tests.

For more info, see: https://github.com/nerdvegas/rez/wiki/Package-Definition-Guide#tests

RELEASE 2.6.2: Issue #392: import in package.py breaks installation

Fixes #392

RELEASE 2.6.1: PR #374: create a set of standard build env vars

Merged: #374
See: https://github.com/nerdvegas/rez/wiki/Environment-Variables#resolved-build-environment-variables

RELEASE 2.5.3: Bugfixes, More Tests

This release fixes various issues found in the previous three releases. It also adds some tests for the new package.py features introduced in 2.5.0.

RELEASE 2.5.2: PR #378: Avoid trying to create the .building file while running rez build

Addresses PR #378: #378

RELEASE 2.5.1: PR #354: build_process.local: _build_variant_base - if shutil.copy fails, try replacing

Addresses PR: #354

RELEASE 2.5.0: package.py: Preprocessing, Shared Code, Function Attributes, Requirements Expansion

This release adds a number of co-related features:

• Package preprocessing (see https://github.com/nerdvegas/rez/wiki/Package-Definition-Guide#package-preprocessing);
• Shared code in package.py files (see https://github.com/nerdvegas/rez/wiki/Package-Definition-Guide#sharing-code-across-package-definition-files);
• Package attributes as early-/late- binding functions (see https://github.com/nerdvegas/rez/wiki/Package-Definition-Guide#package-attributes-as-functions).
• Requirements expansion (see https://github.com/nerdvegas/rez/wiki/Package-Definition-Guide#requirements-expansion)

Enjoy.
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