v0.1.2

the utility function pdf_to_xml() is now the worker to convert pdf documents to xml;
invalid xml (happens occasionally) is repaired using xmllint --recover, if availably (issue #3)
bug fix (issue #2) - PDF class can now process one-page-documents
bug fix (issue #1) - whitespace in filename does not cause crash
missing whitespace when concatenating lines solved
Unit tests adapted to conform to new handling of whitespace
Package 'knitr' has been moved in DESCRIPTION from "Depends:" to "Suggests:", which is the usual practice.
Package 'magrittr' has been dropped from 'Dependes:' in DESCRIPTION; code using magrittr has been reformulated to avoid using magrittr within a package.
Christoph Leonhardt listed as package author.
To overcome the dependency on the Rpoppler package, which has become inhibiting on the portability of the package, usage of the function Rpoppler::PDF_info() has been replaced by a reliance on pdftools::pdf_info() and pdftools::pdf_pagesize(), respectively.

v0.1.1

bug in method $get_pages() removed that occurrs when there are not text nodes on page
bug removed when adding boxes to existing box data.frame
vignette explains scenario of two column layout now (using two approaches)
moved to R6 class system, replacing reference classes
columns "page" in field $pagesizes and $boxes renamed to page_node (to avoid confusion)
remove_page-method added to PDF class