update readme doc structure

update main title section

clean markdown whitespace

chore(release): 1.5.0

fix(autocomplete): ensure autocomplete is displayed above header actions

chore(CONTRIBUTING.md): add instructions to debug autocomplete dropdown

Merge pull request #64 from algolia/chore/update-images

chore: commit sketch source file

feat(assets): update icons

chore(assets): update images to use aerial design

chore(CONTRIBUTING.md): add some info about releasing on Chrome

chore: fix path to release script

chore(release): 1.4.3

chore: make release script executable

Merge pull request #59 from algolia/limit-web-accesible-resources