Large update of Sphinx doc; moved Sphinx source to dev dir; Cleaned control files

for_developers/Sphinx/source/_static/css/theme_overrides.css

for_developers/Sphinx/source/_static/download_icon.png

...ers/Sphinx/source/_static/fe7.0.4_radon_cc_12-03-2019.png

for_developers/Sphinx/source/_static/guide_icon.png

for_developers/Sphinx/source/_static/help_icon.png

for_developers/Sphinx/source/_static/install_icon.png

for_developers/Sphinx/source/_static/prog_icon.png

for_developers/Sphinx/source/_static/source_icon.png

for_developers/Sphinx/source/authors.rst

for_developers/Sphinx/source/changelog.rst

for_developers/Sphinx/source/conf.py

for_developers/Sphinx/source/dev_guide.rst

for_developers/Sphinx/source/documentation.rst

for_developers/Sphinx/source/ecmwf_data.rst

for_developers/Sphinx/source/evaluation.rst

for_developers/Sphinx/source/first_steps.rst

for_developers/Sphinx/source/index.rst

for_developers/Sphinx/source/installation.rst

for_developers/Sphinx/source/support.rst

run/control/CONTROL_CERA