[trac3891] Fix some typos in the message descriptions

src/bin/dhcp4/dhcp4_messages.mes

@@ -179,26 +179,26 @@ by the Interface Manager until interface is enabled.
 
 % DHCP4_DECLINE_LEASE Address %1 was declined by client %2. The lease will be unavailable for %3 seconds.
 This informational message is printed when a client received an address, but
-discovered that it is used by some other device and notified the server by
-sending DHCPDECLINE message. The server checked that this address really was
-leased to a given client and marked this address as unusable for a certain
+discovered that it is being used by some other device and notified the server by
+sending a DHCPDECLINE message. The server checked that this address really was
+leased to the client and marked this address as unusable for a certain
 amount of time. This message may indicate a misconfiguration in a network,
 as there is either a buggy client or more likely a device that is using an
 address that it is not supposed to. The server will fully recover from this
-situation, but if the underlying problem of misconfigured or rogue device
+situation, but if the underlying problem of a misconfigured or rogue device
 is not solved, this address may be declined again in the future.
 
 % DHCP4_DECLINE_LEASE_NOT_FOUND Received DHCPDECLINE for addr %1, but no such lease found. Client: %2
 This warning message indicates that a client reported that his address was
-detected as a duplicate (i.e. other device in the network is using this address).
-However, the server hoes not have a record for this address. This may indicate
-client's error or purged server's database.
+detected as a duplicate (i.e. another device in the network is using this address).
+However, the server does not have a record for this address. This may indicate
+a client's error or a server's purged database.
 
 % DHCP4_DECLINE_LEASE_MISMATCH Received DHCPDECLINE for addr %1 from %2, but the data doesn't match: received hwaddr: %3, lease hwaddr: %4, received client-id: %5, lease client-id: %6
-This informational message means that a client attempts to report his address
+This informational message means that a client attempted to report his address
 as declined (i.e. used by unknown entity). The server has information about
 a lease for that address, but the client's hardware address or client identifier
-do not match the server's stored information. Client's request will be ignored.
+does not match the server's stored information. The client's request will be ignored.
 
 % DHCP4_DHCID_COMPUTE_ERROR failed to compute the DHCID for lease: %1, reason: %2
 This error message is logged when the attempt to compute DHCID for a specified