Remove unused images

src/client/components/main_layout/Main.js

src/client/components/main_layout/MainCard.js

src/client/components/main_layout/TopBar.js

src/client/components/perspectives/sampo/Footer.js

src/client/configs/sampo/PerspectiveConfig.js

src/client/containers/SemanticPortal.js

src/client/img/actors-452x262.jpg

src/client/img/actors-452x262_2.jpg

src/client/img/logos/Aalto_SCI_EN_13_BLACK_2_cropped.png

src/client/img/logos/cnrs-logo-white-small.png

...nt/img/logos/funders/Agence_Nationale_de_la_Recherche.png

src/client/img/logos/funders/aka_en_vaaka_rgb.jpg

src/client/img/logos/funders/cropped-logo_tap_0_.png

src/client/img/logos/funders/did_logo.png

src/client/img/logos/funders/imls_logo_2c_cropped.jpg

src/client/img/logos/heldig-logo-transparent-black.png

...lient/img/logos/kotus-logo-white-no-backgrounds-small.png

src/client/img/logos/namesampo.png

src/client/img/logos/oxford-logo-white.png

src/client/img/logos/partners/13_9_04_logo_cropped_small.png