update changelog for version 0.17

release version 0.16.0

Merge pull request PHPOffice#1429 from PHPOffice/develop

Merge 0.15 to master

Release v0.14.0

Updated change log.

Merge pull request PHPOffice#605 from PHPOffice/hotfix-0.12.1

Hotfix 0.12.1

Merge pull request PHPOffice#460 from PHPOffice/develop

v0.12.0

Bugfix for PHPOffice#257: HTML Reader: `<p>` and header tags puts no …

…output

Merge pull request PHPOffice#256 from PHPOffice/develop

PR 0.11.0

Merge pull request PHPOffice#247 from ivanlanin/master

PR 0.10.1