problem: ci doesn't build with nss

Solution: add an nss build to CI

.travis.yml

@@ -44,6 +44,13 @@ matrix:
   - env: BUILD_TYPE=default CURVE=tweetnacl IPv6=ON
     os: linux
     dist: precise
+  - env: BUILD_TYPE=default CURVE=tweetnacl USE_NSS=yes
+    os: linux
+    dist: precise
+    addons:
+      apt:
+        packages:
+          - libnss3-dev
   - env: BUILD_TYPE=coverage CURVE=tweetnacl DRAFT=enabled
     os: linux
     addons:

ci_build.sh

@@ -24,6 +24,10 @@ if [ $BUILD_TYPE == "default" ]; then
         CONFIG_OPTS+=("LDFLAGS=-fuse-ld=gold")
     fi
 
+    if [ $USE_NSS == "yes" ]; then
+        CONFIG_OPTS+=("--with-nss")
+    fi
+
     if [ -z $CURVE ]; then
         CONFIG_OPTS+=("--disable-curve")
     elif [ $CURVE == "libsodium" ]; then