Add sorting to tables

[Laoujin]

Allow sorting on tables.

For consultant names: should be able to sort on last name and first name.

Or maybe we need to display consulants like "LastName FirstName" instead --> to be checked with back office (check met Jelle)
(or maybe this could be configuration?)

[Laoujin]

Hover over the th cell --> show sort icons
Click on sort icons to toggle between: no sort, asc, desc

If no sorting is present then use the custom or default sort (this is sometimes a special sorting, ex in Projects)
If it makes no sense, return null to disable sorting on this column.

{
    key: 'type',
    value: m => t(`consultant.types.${m.type}`),
    // no sort present, sort on the value
}

{
    key: 'buttons',
    header: {title: '', width: 110},
    value: m => <EditIcon onClick={`/consultants/${m.slug || m._id}`} style={{marginRight: 15}} size={1} />,
    // makes no sense to sort on this column, return null to disable sorting for the column
    sort: null
  }

For sorting, check the type of the object to decide how to sort:

• numbers --> weird in javascript!! (ex: sort [1, 10, 100]...)
• dates/moments --> valueOf
• strings --> localeCompare
• etc...

Optional:
Sort on multiple columns by pressing shift + click

[Laoujin]

Belangrijk: bij project months: sorteren op "Project" (eerste kolom) --> sorteer op "consultant.firstName consultant.lastName"