Columns width, minWidth and maxWidth could be set to 'fitContent'

[landre3567]

We mainly use the fitColumns layout but non growing colmns must have a 'width' set in pixels.

We don't want to hardcode the 'with' and we would like to set the non growing column width to fits its data (like in fitData layout).

We propose to not limit the 'width' parameter to pixels values.
'width' could be set with the magic value 'fitContent' so the width could be calcuated dynamicaly

Instead of

{
layout: "fitColumns",
columns : [
{
field: "id",
title: "Id",
width: 90,
},
{
field: "name",
title: "Name",
widthGrow: 100,
}
]
}

We could use

{
layout: "fitColumns",
columns : [
{
field: "id",
title: "Id",
width: 'fitContent',
},
{
field: "name",
title: "Name",
widthGrow: 100,
}
]
}

'fitContent' could be also applied to minWidth ans maxWidth