Configurable MaxNumberOfOptions before select layout changeds

[itweserems]

When using dynamic fields of type "dropdown" or "multiselect", the default code-setup is that the layout of a select-field (e.g. dynamic field) will be changed when the amount of selectable values is above 1000.

This is for performance reasons, but the limit should be configurable. The layout for fields with >1000 values does not allow searching values and with a configurable maximum number can be set to an individual level to keep the search functionality as long as performance goes along with this.

Attached a screenshots that contains both field layouts, below and above 1000 selectable values.