MULE-6731 - with big files and low polling frequency file inbound enpdoint consumes the same file several times
(cherry picked from commit 062621d7256f1304bbe0a9f39c11d634027fa687)

Conflicts:
	transports/file/src/main/java/org/mule/transport/file/FileMessageReceiver.java
	transports/file/src/main/java/org/mule/transport/file/ReceiverFileInputStream.java
(cherry picked from commit 546568c621ff80b42429b9edf746246545e9124f)

Conflicts:
	transports/file/src/main/java/org/mule/transport/file/FileMessageReceiver.java
(cherry picked from commit e76878afdf0727bb232d2bf54605ed9a7e7e704d)

Conflicts:
	transports/file/src/main/java/org/mule/transport/file/FileMessageReceiver.java
	transports/file/src/test/java/org/mule/transport/file/FileMessageReceiverMessageProcessingTestCase.java