Precedence of assets in TemplateObjects

[e-picas]

We have to find a way to ask the TemplateEngine to write its assets files in a certain order ...

Typically, the "css/styles.css" must be last even if a preset loads its files after to keep the override features ...

It may causes some problems:

• the order must be kept when merging or, more complex, when minifying (with an already minified CSS file in the middle of the stack for example ...)
• the order may be flexible ...

This is the next TODO ?