Issue #307: fix API regresssions
- allow strings with dots in router script for API calls
- double escape slashes when searching for an entity (Apache needs that)
- fix perfect_match search on string search returning no result
- adapt dev server script to run outside of the web folder (needed to allow dots in urls)
- change dev server port to 8082 (less likely to collide with another instance)
- fallback values for all search options set before the redirect,  "/?recherche=test&json" -> "api/v1/search/strings/release/en-US/fr/test/"
- updated README