feature: Add postprocessing code, tables and figures

[aldeav]

Signed-off-by: aldeav akandoria@gmail.com

Pull Request Template

Description

Addition of postprocessing code (in R) for GCBM Carpathians. It outputs figures and tables for the 5 lifezones in the Carpathians for 4 indicators - Deadwood, Litter, Soil Carbon and Total Biomass.

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• I have checked my code and corrected any misspellings
• I have signed the commit message to agree to Developer Certificate of Origin (DCO) (to certify that you wrote or otherwise have the right to submit your contribution to the project.) by adding "--signoff" to my git commit command.

Kindly review the PR @aornugent