add test without curl

.travis.yml

@@ -1,8 +1,11 @@
 language: c # defaults to ruby
 install:
   - sudo apt-get install ksh zsh -y
+  - '[ -z "$WITHOUT_CURL" ] || sudo apt-get remove curl -y'
 before_script:
-  - curl -o /tmp/urchin https://raw.githubusercontent.com/scraperwiki/urchin/master/urchin && chmod +x /tmp/urchin
+  - '[ -n "$WITHOUT_CURL" ] || curl -o /tmp/urchin https://raw.githubusercontent.com/scraperwiki/urchin/master/urchin'
+  - '[ -z "$WITHOUT_CURL" ] || wget -O /tmp/urchin https://raw.githubusercontent.com/scraperwiki/urchin/master/urchin'
+  - chmod +x /tmp/urchin
 script:
   - NVM_DIR=$TRAVIS_BUILD_DIR make TEST_SUITE=$TEST_SUITE URCHIN=/tmp/urchin $SHELL
 env:
@@ -12,3 +15,4 @@ env:
   - SHELL=zsh TEST_SUITE=fast
   - SHELL=ksh TEST_SUITE=fast
   - SHELL=sh TEST_SUITE=slow
+  - SHELL=sh TEST_SUITE=fast WITHOUT_CURL=1