[IMP] Cache bundles in ir.attachments instead of a LRU

Forward ported from 8.0's commit: 8402625
[FIX] mail: bad test
[IMP] hr: strenghtening of write()
[FIX] bundles: fix compiled css assets recomposition

- Do not include css in less source because malformed css will break
  less compilation
- Always recompose compiled css, even if not in debug mode
- Less and sass compilers mode @at-rules on top in order to comply
  to css 2.1, those @at-rules where left-over during the recompostion
  because they lost their marker. Those are now handled as virtual
  inline stylesheets.
[FIX] ir.attachments of compiled css assets not properly invalidated
[IMP]:Improve currency EUR to USD

[IMP]:Improve float_compare set a precision

[IMP]:use a currency eur to usd in l10n_be_coda