Moved "Development Setup" from "README.md" to "CONTRIBUTING.md" so that "README.md" is conciser.

CHANGELOG.md:
- Added the section "# Changelog: Vadere" and corrected indention level of following sections.
- Also adapted the correspoding guide "Writing Changelog Entries.md".
4 jobs for master in 102 minutes and 23 seconds
Status Name Job ID Coverage
  Test
passed unit_tests_with_coverage #390370

00:01:00

18.0%
 
  Deploy
failed run_origin_test #390371

00:00:50

failed run_scenario_files #390373

01:02:46

failed run_seed_test #390372

00:37:46

 
Name Stage Failure
failed
run_scenario_files Deploy
Finished scenario file (40.3 s): VadereModelTests/TestOSM/scenarios/rimea_04_flow_osm1_550_up.scenario
###########
# Summary #
###########

Total scenario runs: 125
Passed: 109
Failed: 16
ERROR: Job failed: exit status 1
failed
run_origin_test Deploy
Finished processing dependencies for VadereAnalysisTool==0.1.0
$ python3 Tools/ContinuousIntegration/run_orign_translation_test.py
Traceback (most recent call last):
File "Tools/ContinuousIntegration/run_orign_translation_test.py", line 91, in <module>
output_pairs = get_output_pairs()
File "Tools/ContinuousIntegration/run_orign_translation_test.py", line 66, in get_output_pairs
output_without_offset = [d for d in os.listdir(path) if d.endswith("without_offset")]
FileNotFoundError: [Errno 2] No such file or directory: 'Tools/ContinuousIntegration/run_orign_translation_test.d/output'
ERROR: Job failed: exit status 1
failed
run_seed_test Deploy
Scenario complex_NAVIGATION_001 with scenario-hash 356d67cb336d615abf2e9d0d29471194 - OK
###########
# Summary #
###########

Total scenario runs: 7
Passed: 6
Failed: 1
ERROR: Job failed: exit status 1