Simplify CI

Move actual CI tests into .travis.yml, and simplify the Debian packaging
Makefile as a result. Feel free to re-add package building to Travis as
another entry in the `scripts:` array.

.travis.yml

@@ -1,22 +1,15 @@
-language: go  # Use go language for shfmt
-go:
-  - master
-
-# Use container-based infrastructure for quicker build start-up
-sudo: false
+language: minimal
 
 addons:
   apt:
     sources:
-    - debian-sid    # Grab shellcheck from the Debian repo (o_O)
-    packages:
     - shellcheck
 
-install:
-  - go get -u github.com/mvdan/sh/cmd/shfmt
+before_install:
+  - go get -u mvdan.cc/sh/cmd/shfmt
 
 script:
- - make check
-
-matrix:
-  fast_finish: true
+  - shellcheck -e SC1091 acts
+  - shfmt -i 4 -d acts
+  - shellcheck -e SC2034 acts.conf.sample
+  - shfmt -i 4 -d acts.conf.sample

Makefile

@@ -5,12 +5,6 @@ package: dist/acts_$(VERSION)_all.deb
 clean:
 	rm -rf dist
 
-check:
-	shellcheck -s sh -f gcc -e SC1091 acts
-	shellcheck -s sh -f gcc -e SC2034 acts.conf.sample
-	@ echo shfmt -l -i 4 acts acts.conf.sample
-	@ [ -z $(shell shfmt -l -i 4 acts acts.conf.sample) ] || { echo $(shell shfmt -l -i 4 acts acts.conf.sample) && exit 1; }
-
 dist/acts_$(VERSION)_all.deb: dist
 	@ fpm \
 		-s dir \
@@ -39,5 +33,4 @@ dist:
 
 .PHONY: \
 	package \
-	check \
 	clean