[3689] Added new host test file

Addressing more review comments...

new file - host_unittest.cc
    contains Dhcp6Client based host reservation tests

dhcp6_client.cc
dhcp6_client.h
    added setDuid(str) method to allow duid to be set to
    specific value

dhcp6_srv_unittest.cc -
    deleted host reservation tests, now in host_unittest.cc

dhcp6_test_utils.cc
dhcp6_test_utils.h
    deleted createHost6() method

1 files changed, 6 insertions, 0 deletions

diff --git a/src/bin/dhcp6/tests/dhcp6_client.cc b/src/bin/dhcp6/tests/dhcp6_client.cc
index 73720695a9..8f445ec882 100644
--- a/src/bin/dhcp6/tests/dhcp6_client.cc
+++ b/src/bin/dhcp6/tests/dhcp6_client.cc
@@ -426,6 +426,12 @@ Dhcp6Client::getLeasesByIAID(const uint32_t iaid) const {
 }
 
 void
+Dhcp6Client::setDUID(const std::string& str) {
+    DUID d = DUID::fromText(str);
+    duid_.reset(new DUID(d));
+}
+
+void
 Dhcp6Client::modifyDUID() {
     if (!duid_) {
         duid_ = generateDUID(DUID::DUID_LLT);