Folia-tools

* [foliavalidator] added a --fixinvalidreferences parameter to fix (=delete) invalid wref references (proycon/flat174)
* [folia2txt] implemented support for retrieving the original text of a document prior to any corrections 40

* folia2columns: added option to extract sentences and paragraphs and support for extracting sequences of lemmas, pos, poshead, sense or phon when extracting paragraphs or sentences (thanks to Jelke Bloem) 36 37
* folia2columns: if outputting to a single file, no longer print header multiple times when processing multiple files (thanks to Jelke Bloem)
* tei2folia: implemented an --intermediate option to dump intermediate output
* tei2folia: can handle certain pseudo-TEI now 35
* fix for table in pseudo-TEI paragraph
* Accept teiTrim as a valid root element, despite this NOT being an actual valid TEI element!
* foliaspec: added a mapping to the C++ properties (Ko van der Sloot)
* foliahtml: updated folia2html test output
* python 3.5 is deprecated now, use 3.6 or higher

* folia2html: Adapted whitespace handling to comply to FoLiA v2.5; result in less pretty-printed HTML output but more true to the original FoLiA 29
* folia2html: removed broken -o option, just rely on redirection 27
* folia2html: handle t-ref 32
* folia2html: implemented t-hspace
* folia2html: FoLiA comments should translate to html comments 33

Bugfix release, previous release was premature.

folia2html: Implemented support for outputting based on other text classes 30

* folia2html: translate t-hbr as a soft-hyphen
* folia2html: translate features on structural elements to css classes
* folia2html: fix in translating t-str to css classes
* foliasplit: prevent duplicate IDs in the root element