Filetype.Types build update bug

[loleg]

After a package update (see #214) there is a build error as follows:

# github.com/ProxeusApp/proxeus-core/sys/validate
sys/validate/file.go:47:3: cannot use filetype.Types (type sync.Map) as type map[string]types.Type in field value
make: *** [Makefile:83: update] Error 2

This is most likely due to the package https://github.com/h2non/filetype switching to sync.Map.

[loleg]

I figure something like this would need to happen in sys/validate/file.go

        exactTypes := map[string]types.Type
        filetype.Types.Range(func (value types.Type) bool {
	  exactTypes[key] = value
	  return true
         })

Before adding to ftRepository.Exact

[loleg]

Or just by changing the Exact definition to sync, I am sidestepping the problem.. needs testing, of course!