Build with stack

- build with stack lts-3.8 default settings

.gitignore

@@ -1,3 +1,4 @@
 .cabal-sandbox/
 cabal.sandbox.config
 dist/
+.stack-work/

stack.yaml

@@ -0,0 +1,29 @@
+# For more information, see: https://github.com/commercialhaskell/stack/blob/master/doc/yaml_configuration.md
+
+# Specifies the GHC version and set of packages available (e.g., lts-3.5, nightly-2015-09-21, ghc-7.10.2)
+resolver: lts-3.8
+
+# Local packages, usually specified by relative directory name
+packages:
+- '.'
+
+# Packages to be pulled from upstream that are not in the resolver (e.g., acme-missiles-0.3)
+extra-deps: []
+
+# Override default flag values for local packages and extra-deps
+flags: {}
+
+# Control whether we use the GHC we find on the path
+# system-ghc: true
+
+# Require a specific version of stack, using version ranges
+# require-stack-version: -any # Default
+# require-stack-version: >= 0.1.4.0
+
+# Override the architecture used by stack, especially useful on Windows
+# arch: i386
+# arch: x86_64
+
+# Extra directories used by stack for building
+# extra-include-dirs: [/path/to/dir]
+# extra-lib-dirs: [/path/to/dir]