Update 00-intro.md
Add test case for removing unused dependencies on whitelisted update
Add test to verify that depency packages get deleted when no longer in lock file
fixes composer/composer#3546
Merge pull request #3547 from alcohol/fix-reflection

fix reflection implementation in EventDispatcher
Enhancement: Add sort-packages option which allows sorting of packages
Merge pull request #3549 from localheinz/feature/sort-dependencies

Enhancement: Add sort-packages option which allows sorting of packages
Fix HHVM interop
Point users at troubleshooting if they get known exceptions
Merge remote-tracking branch 'PaulSchell/patch-1'
Fix wording, refs #3466
Merge pull request #3467 from naderman/fix-update-whitelist-unused

Add test case for removing unused dependencies on whitelisted update
Fix parsing of strings, fixes #3543
Avoid loading plugins that have had their code wiped from filesystem, fixes #3115, closes #3538
Enough intermittent failures already
Make sure global plugins are purged as well, fixes #3115
Suppress errors when creating global composer
Fix bug when installing
Fix tests