Bump version of pdf-js, typescript and react related dependencies

Hopefully fixes #77 (closed). Could possible lead to better performance.

Imports pdfjs-dist/webpack instead of pdfjs-dist. The webpack file reexports index.js but also saves the worker url using a web pack loader. The new version is required as the old types do not include the webpack build and the new types don't match the old pdfs version this project was using.

See issue description for a detailed explanation of why these packages have to be updated simultaneously.