singr 4.3.0

• update to R version 4.3.0
• update to Ubuntu 22.04
• remove extra libraries
• simplify README

4.1.3

• use R version 4.1.3
• switch to ubuntugis unstable for later gdal version
• entrypoint is now a shell instead of R
• fix problem with test

4.1

• move to R v4.1
• install V8 sysdeps

4.0

upgrade to R 4.0 and Ubuntu 20.04

3.6

Initial release using Ubuntu 18.04 and R version 3.6