Make use of new ValidateResult static fields

In an effort to minimise unnecessary object creation, the following static fields have been added to the ValidateResult class:

Public Shared [Error] As New ValidateResult(ValidateStatuses.Error)
Public Shared Failed As New ValidateResult(ValidateStatuses.Failed)
Public Shared OK As New ValidateResult(ValidateStatuses.OK)
Public Shared Unknown As New ValidateResult(ValidateStatuses.Unknown)
Public Shared Unsupported As New ValidateResult(ValidateStatuses.Unsupported)
Public Shared Warning As New ValidateResult(ValidateStatuses.Warning)

Error, Failed, and Warning don't have static fields as they typically include a custom message.

Make all of the below plugins use these new static fields.

[x] Method.Attributes
[x] Method.BatchedAtoZ
[x] Method.Checksum
[x] Method.Classification
[x] Method.Consolidate
[x] Method.Content
[x] Method.DateStamp
[x] Method.Delimiter
[x] Method.Exif
[x] Method.Extension
[x] Method.FindReplace
[x] Method.Mirror
[x] Method.NamingMask
[x] Method.ParentRename
[x] Method.Quantity
[x] Method.Rules
[x] Method.StandardAtoZ
[x] Method.Substring
[x] Method.Tag
[x] Modifier.Attributes
[x] Modifier.Casing
[x] Modifier.DateStamp
[x] Modifier.FindReplace
[x] Trigger.DateTime
[x] Trigger.DirectoryWatcher
[x] Trigger.UserIdle

BootBlock / FileSieve

Make use of new ValidateResult static fields #88