Add option to suppress permissive types

[jdforsythe]

Fixes #2839

Allows suppressing the permissive types with --suppressPermissiveTypes=true

In combination with --outputTemplate="%s", replaces the permissive types with the restrictive types using the default message name (without __Output).

[murgatroid99]

This also impacts the output of the generateService* functions, because they currently use both the permissive and restrictive types. I think it might be enough to modify useNameFmter with a branch for this flag, but I'm not 100% sure.