[release_table] Improve script

[marcwrobel]

• Add strict typing to the fields. This makes the script fail if some column does not have the expected type (for example because of a change in the HTML page).
• Support regex and templating for all fields (not only the releaseCycle). This make it possible to extract only the necessary information without having to do some sort of 'magic' cleanup (replacements in dates have been reverted).
• Do not inject 'releaseCycle' anymore in the JSON (there is already the name).

[marcwrobel]

Expected updates (and errors). Merging.