support SASL tests on Travis CI
Merge pull request #419 from phlipper/sasl-ci

Support SASL tests on Travis CI
Remove install software-properties-common
Ignore gemfiles/vendor
Fix local vars on rack session test
Make sure client is alive on Rack store.

In order to be compatible with main rack memcache store https://github.com/rack/rack/blob/4defbe5d7c07b3ba721ff34a8ff59fde480a4a9f/lib/rack/session/memcache.rb#L37
Return false if session_id is nil
Changelog entry
Merge pull request #423 from arthurnn/fix_rack_store

Fix rack store
Merge pull request #422 from arthurnn/fix_build

Attempt to fix the build
Document breaking API change, fixes #424
Merge branch 'master' of github.com:mperham/dalli
docs for config alongside ENV["MEMCACHE_SERVERS"]

documentation addressing question in #285
Accommodate nil server setting via ActiveSupport

see also #426
Merge pull request #427 from jjb/allow-nil-server-config

Accommodate nil server setting via ActiveSupport
Merge pull request #426 from jjb/document-env-servers-config

docs for config alongside ENV["MEMCACHE_SERVERS"]
Add test for existing server hostname parsing
Add ipv6 address support
Add IPv6 note to changelog
Remove unused require of memcached_mock