Add pattern for buttercup to not run gists.github.com on travis

We just get 403 Forbidden back from gists anyways when running on
travis. That makes it not worth it.

Makefile

@@ -1,6 +1,11 @@
+TRAVIS ?= false
 EMACS ?= emacs
 CASK ?= cask
 
+ifeq ($(TRAVIS),true)
+	PATTERN=--pattern 'can paste with \([^g]\|g[^i]\|gi[^s]\)'
+endif
+
 all: test
 
 test:
@@ -16,7 +21,7 @@ unit:
 
 # Run all tests in tests/integration/
 integration:
-	${CASK} exec buttercup -L . tests/integration/
+	${CASK} exec buttercup -L . tests/integration/ ${PATTERN}
 
 build:
 	${CASK} build