add favicons

...ech/static_src/src/images/favicons/android-chrome-144.png

opentech/static_src/src/images/favicons/apple-icon-120.png

opentech/static_src/src/images/favicons/apple-icon-152.png

opentech/static_src/src/images/favicons/apple-icon-180.png

opentech/static_src/src/images/favicons/apple-icon-76.png

opentech/static_src/src/images/favicons/browserconfig.xml

opentech/static_src/src/images/favicons/favicon-16.png

opentech/static_src/src/images/favicons/favicon-32.png

opentech/static_src/src/images/favicons/mstile-150.png

...tech/static_src/src/images/favicons/safari-pinned-tab.svg

opentech/static_src/src/images/favicons/site.webmanifest

opentech/templates/base-apply.html

opentech/templates/base.html

public/favicon.ico