Initial Extruder Speed - Layer and Part Specific Settings

## Expected Behavior
The ability to adjust initial extruder speed on a part or layer specific basis.

## Actual Behavior
Only a global value is passed to the writer.

## Possible Solution
Self-Explanatory

## Steps to Reproduce the Problem
Self-Explanatory.  Ideally, bullet or numbered list.

## Specifications
Easily tested with Cincinnati Syntax
