`0.1.5` CHANGELOG update pre-publish.

`0.1.5` CHANGELOG update pre-publish.

Adds:
* FilePackagesDirectoryPackages.getBase(..)` performance improvements.

BUG=
R=scheglov@google.com

Committed: https://github.com/dart-lang/package_config/commit/f77965f842444dd0f2de4ad6f994b2ed33e0254d

[pquitslund, 2016-06-09 15:59:25]

pquitslund@google.com changed reviewers:
+ scheglov@google.com

[pquitslund, 2016-06-09 16:00:01]

Description was changed from

==========
Version bump to `0.1.5` pre-publish.

Adds:
* FilePackagesDirectoryPackages.getBase(..)` performance improvements.

BUG=
==========

to

==========
`0.1.5` CHANGELOG update pre-publish.

Adds:
* FilePackagesDirectoryPackages.getBase(..)` performance improvements.

BUG=
==========

[scheglov, 2016-06-09 16:00:33]

LGTM

[pquitslund, 2016-06-09 16:01:00]

Description was changed from

==========
`0.1.5` CHANGELOG update pre-publish.

Adds:
* FilePackagesDirectoryPackages.getBase(..)` performance improvements.

BUG=
==========

to

==========
`0.1.5` CHANGELOG update pre-publish.

Adds:
* FilePackagesDirectoryPackages.getBase(..)` performance improvements.

BUG=
R=scheglov@google.com

Committed:
https://github.com/dart-lang/package_config/commit/f77965f842444dd0f2de4ad6f9...
==========

[pquitslund, 2016-06-09 16:01:02]

Committed patchset #1 (id:1) manually as
f77965f842444dd0f2de4ad6f994b2ed33e0254d (presubmit successful).