* feat(server): add landing page
Fixesorhun/rustypaste#13
* feat(server): allow using {REPOSITORY} in landing page
* fix(server): Get rid of unused import, add line about expiration
* chore(fmt): cargo fmt
* fix(tests): inject app data for fixing index test
* feat(server): redirect to GitHub repository if landing page is not specified
* test(fixtures): add fixture test for landing page
Co-authored-by: Orhun Parmaksız <orhunparmaksiz@gmail.com>