soeretypo: HTML5 validation

[Olivier Maury]

Continuous integration failed for HTML5 validation on 2 pages, the errors are:

- soeretypo/extraction/metadata_authors
  - The width attribute on the table element is obsolete. Use CSS instead.
  - The cellpadding attribute on the table element is obsolete. Use CSS instead.
  - A table row was 4 columns wide, which is less than the column count established by the first row (5).
  - The align attribute on the td element is obsolete. Use CSS instead.
  - Table column 5 established by element th has no cells beginning in it.

- soeretypo/extraction/metadata_pros_infos
  - The for attribute of the label element must refer to a form control.

[Olivier Maury (olivier-maury)]

Another page is not valid:

- soeretypo/extraction/metadata_chemical_compositions_dist
  - Line 163, Column 250: No p element in scope but a p end tag seen.
  - Line 164, Column 895: Attribute alt not allowed on element div at this point.
  - Line 164, Column 905: No p element in scope but a p end tag seen.