[2545] Separated build and commit phase for all DHCPv4 config parsers.

... also added new BooleanParser.

src/bin/dhcp4/tests/config_parser_unittest.cc

@@ -389,9 +389,9 @@ TEST_F(Dhcp4ParserTest, poolOutOfSubnet) {
 
     EXPECT_NO_THROW(status = configureDhcp4Server(*srv_, json));
 
-    // returned value must be 2 (values error)
+    // returned value must be 1 (values error)
     // as the pool does not belong to that subnet
-    checkResult(status, 2);
+    checkResult(status, 1);
 }
 
 // Goal of this test is to verify if pools can be defined

src/lib/dhcpsrv/subnet.cc

@@ -77,8 +77,8 @@ void Subnet4::addPool4(const Pool4Ptr& pool) {
 
     if (!inRange(first_addr) || !inRange(last_addr)) {
         isc_throw(BadValue, "Pool4 (" << first_addr.toText() << "-" << last_addr.toText()
-                  << " does not belong in this (" << prefix_ << "/" << prefix_len_
-                  << ") subnet4");
+                  << " does not belong in this (" << prefix_.toText() << "/"
+                  << static_cast<int>(prefix_len_) << ") subnet4");
     }
 
     /// @todo: Check that pools do not overlap