unify capitalization of set items and delete no longer used sets

[fbenke-pik]

Purpose of this PR

The PR solves problems with inconsistent capitalization of set items related to gases and is part of the efforts here

This PR removes some sets RCP_regions_world_bunkers, RCP_regions_world and emiRCP that are no longer used in the code.

The set emisForEmiFac11 is adjusted, so that the items SO2, BC and OC are now written lowercase to match the convention for these gases across REMIND.

This set is used to read in data from f11_emifacs_sectREMIND_sourceCEDS.cs4r and f11_emifacs_sectREMIND_sourceGAINS.cs4r and the gases were probably capitalized, because of the input data, but it does not seem necessary.

Type of change

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Do not delete any lines. This makes it easier to understand which areas are affected by your changes and which are not.

Parts concerned

• ☑️ GAMS Code
• ◻️ R-scripts
• ◻️ Documentation (GAMS incode documentation, comments, tutorials)
• ◻️ Input data / CES parameters
• ◻️ Tests, CI/CD (continuous integration/deployment)
• ◻️ Configuration (switches in main.gms, default.cfg, and scenario_config*.csv files)
• ◻️ Other (please give a description)

Impact

• ◻️ Bug fix
• ☑️ Refactoring
• ◻️ New feature
• ◻️ Change of parameter values or input data (including CES parameters)
• ☑️ Minor change (default scenarios show only small differences)
• ◻️ Fundamental change of results of default scenarios

Checklist

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In the end all checkboxes must be ticked before you can merge.

• I executed the automated model tests (make test) after my final commit and all tests pass (FAIL 0)
• I adjusted the reporting in remind2 if and where it was needed
• I adjusted the madrat packages (mrremind and other packages involved) for input data generation if and where it was needed
• My code follows the coding etiquette
• I explained my changes within the PR, particularly in hard-to-understand areas
• I checked that the in-code documentation is up-to-date
• I adjusted forbiddenColumnNames in readCheckScenarioConfig.R in case the PR leads to deprecated switches
• I updated the CHANGELOG.md correctly (added, changed, fixed, removed, input data/calibration)

Further information (optional)

• Runs with these changes are here:
• Comparison of results (what changes by this PR?):

[fbenke-pik]

This set is used to read in data from f11_emifacs_sectREMIND_sourceCEDS.cs4r and f11_emifacs_sectREMIND_sourceGAINS.cs4r here. The gases were probably capitalized, because of the input data, but it looks like GAMS does not care.