Apex Class - Metadata API - copy Lead fields to another object

I need an Apex class (and unit tests). I want to be able to execute a method on the class from the Developer Console to copy custom Lead fields to a custom object called Request__c.

You must utilise this wrapper class for the Salesforce metadata api - https://github.com/financialforcedev/apex-mdapi.

The class method should –

1. Read all the custom fields on the Lead object and add identical fields on a custom object called Request__c.
2. If a field with the same api name already exists on Request__c it should skip and not fail/error
3. Work for the following field types: - Checkbox, Currency, Date, Date/Time, Email, Number, Percent, Phone, Picklist, Picklist (Multi-Select), Text, Text Area, Text Area (Long), Text Area (Rich), URL
4. Create numeric or currency fields with the same precision/decimal places
5. Create text/long text fields with the same length
6. Should copy the required/not required property
7. Create picklists with the same values and api names (which may be different)
7. Create picklists with the same restricted/unrestricted property
9. Set field access to visible for all custom profiles and System Administrator
10. Include unit tests with appropriate coverage for deployment

I have a Developer org with some test fields setup on the Lead and you will have access to this.