[3720] Typo and ChangeLog per review

ChangeLog

+xxx.	[doc]		sar
+	Added sections on LFC to the administrators and developers
+	guides.
+	(Trac #3720, git )
+
 907.	[doc]		tmark
 	Corrected depictions of kea-admin command line options for
 	database-name in Kea Administrator Reference. Prior to this

src/bin/lfc/lfc.dox

@@ -43,7 +43,7 @@ from either the config file or from defaults.
 
 kea-lfc is built on the isc::lfc::LFCController class.  Effectively this provides
 a single external routine, isc::lfc::LFCController::launch, which is called with
-the arguments fromt the command line and proceeds to parse the arguments and
+the arguments from the command line and proceeds to parse the arguments and
 then process the lease files.
 
 It uses isc::util::PIDFile to manipulate a PID file to mediate access to the