New command: Create PowerApps component framework project structure #952

Creates new PowerApps component framework project

pa pcf init --namespace <namespace> --name <name> --template <template>

• namespace: string value, with some limitations (need to decompile PAC)
• name: string value, with some limitations (need to decompile PAC)
• template: enum value, only field and dataset are currently possible

Equivalent to the PowerApps CLI command.