ordered imports (mainly moved to the top of the module)

da/analysis/expand_fluxes.py

da/analysis/expand_mixingratios.py

da/analysis/tools_country.py

da/analysis/tools_regions.py

da/analysis/tools_time.py

da/ct/obspack.py

da/ct/statevector.py

da/platform/capegrim.py

da/platform/huygens.py

da/platform/jet.py

da/platform/maunaloa.py

da/tm5/observationoperator.py

da/tools/initexit.py

da/tools/io4.py

da/tools/rc.py

da/tools/rcn.py