First attempt of github ci

.github-ci.sh

@@ -0,0 +1,71 @@
+#!/bin/sh
+
+edo()
+{
+	printf "\\033[0;34m%s\\033[0m\\n" "$*" 1>&2
+    "$@" || exit 2
+}
+
+edo rm .available-versions
+edo rm .download-urls
+
+# install GHCs
+edo ./ghcup -v install 8.2.2
+edo ./ghcup -v install 8.4.3
+edo ./ghcup -v -c install 8.6.1
+
+# set GHC
+edo ./ghcup -v set 8.6.1
+edo ./ghcup -v set 8.4.3
+
+# rm GHC
+edo ./ghcup -v rm -f 8.6.1
+edo ./ghcup -v rm -f 8.4.3
+
+# reinstall from cached tarball
+edo ./ghcup -v -c install 8.6.1
+edo ./ghcup -v rm -f 8.6.1
+
+# set GHC
+edo ./ghcup -v set 8.2.2
+edo ./ghcup -v rm -f 8.2.2
+
+# install default GHC
+edo ./ghcup -v install
+edo ./ghcup -v set
+
+# install latest GHC
+edo ./ghcup -v install latest
+
+export PATH="$HOME/.cabal/bin:$HOME/.ghcup/bin:$HOME/.local/bin:$PATH"
+edo mkdir -p "$HOME"/.local/bin
+
+edo cp ./ghcup "$HOME"/.local/bin/ghcup
+
+# TODO: exceeds maximum time limit of travis
+# compile GHC from source
+#./ghcup -v compile 8.4.3 ghc-8.2.2
+
+# install cabal-install
+edo ghcup -v install-cabal
+
+edo cabal --version
+
+# install shellcheck
+edo wget https://storage.googleapis.com/shellcheck/shellcheck-latest.linux.x86_64.tar.xz
+edo tar -xJf shellcheck-latest.linux.x86_64.tar.xz
+edo mv shellcheck-latest/shellcheck "$HOME"/.local/bin/shellcheck
+
+# check our script for errors
+edo shellcheck ghcup
+
+edo ghcup -v debug-info
+
+edo ghcup -v list
+edo ghcup -v list -t ghc
+edo ghcup -v list -t cabal-install
+
+edo ghc --version
+
+# self update destructively
+edo ghcup -v upgrade