stack: trial build plan for ghc 8.6 (#883)

[ci skip]

stack-ghc8.6.yaml

@@ -0,0 +1,81 @@
+# stack build plan using GHC 8.6.1 and recent stackage nightly (WIP)
+
+resolver: nightly-2018-10-08
+
+packages:
+- hledger-lib
+- hledger
+- hledger-ui
+- hledger-web
+- hledger-api
+
+allow-newer: true
+
+extra-deps:
+
+# hledger-lib
+- cassava-megaparsec-1.0.0
+- easytest-0.2
+- uglymemo-0.1.0.1
+
+# hledger
+- control-monad-free-0.6.2
+- haskell-src-meta-0.8.0.3
+- here-1.2.13
+- lucid-2.9.10
+- statistics-0.14.0.2
+- vector-binary-instances-0.2.5
+- wizards-1.0.2
+
+# hledger-ui
+- brick-0.41.2
+- config-ini-0.2.3.0
+- data-clist-0.1.2.1
+- text-zipper-0.10.1
+- vty-5.24
+- word-wrap-0.4.1
+
+# hledger-web
+- asn1-encoding-0.9.5
+- asn1-parse-0.9.4
+- asn1-types-0.3.2
+- byteable-0.1.1
+- cipher-aes-0.2.11
+- clientsession-0.9.1.2
+- connection-0.2.8
+- cprng-aes-0.6.1
+- crypto-cipher-types-0.0.9
+- crypto-random-0.0.9
+- cryptonite-conduit-0.2.2
+- email-validate-2.3.2.7
+- http-client-tls-0.3.5.3
+- http-conduit-2.3.2
+- json-0.9.2
+- pem-0.2.4
+- persistent-2.8.2
+- persistent-template-2.5.4
+- securemem-0.1.10
+- skein-1.0.9.4
+- tls-1.4.1
+- wai-app-static-3.1.6.2
+- wai-handler-launch-3.0.2.4
+- x509-1.7.4
+- x509-store-1.6.6
+- x509-system-1.6.6
+- x509-validation-1.6.10
+- yesod-1.6.0
+- yesod-core-1.6.6
+- yesod-form-1.6.2
+- yesod-persistent-1.6.0
+- yesod-static-1.6.0
+
+# hledger-api
+- http-media-0.7.1.3
+- servant-0.14.1
+- servant-server-0.14.1
+- servant-swagger-1.1.5
+- swagger2-2.3
+
+nix:
+  pure: false
+  packages: [perl gmp ncurses zlib]