From upstream
Merge branch 'develop' of https://github.com/PHPOffice/PHPWord.git into develop
Merge branch 'develop' of https://github.com/PHPOffice/PHPWord.git into develop
Merge branch 'develop' of https://github.com/PHPOffice/PHPWord.git into develop
#72: Basic RTF Reader
Merge branch 'rtfreader' into rtf
Merge branch 'develop' of https://github.com/PHPOffice/PHPWord.git into develop
Added Field Element
Travis build error fix
RTF Reader: Split control parsers into functions
Update changelog, docs, and unit tests for new `Field` element #251
Merge branch 'develop' into rtf
RTF reader: Unit tests and some improvements