Made it so that bottom bar hides on zoom.

Updated libraries, including theme engine to eliminate Android Q crash.

Replaced fab with bottom bar.

Removed fab and added a bottom app bar.

Enable opening http and https from intent. Should close #28

Changed version code, version num, and lib versions.

Correct Bug #27

This change correct the error of opening a PDF from the AOSP E-Mail app.

Fixed Travis errors with sdk...

Fixed bug that caused app to crash when pressing appbar back button on
about page, and updated target sdk to 29.

Fixed major printing bug

Fixed major bug that crashed the app, due to Cyanea and the sample pdf
being absent.

Fixed error with string xml file.

Added Russian localization thanks to @Greynar

It's been a long time. Printing has now been implemented. Also, got rid
of sample pdf.

added french translation