Release v2.1.0 solc 0.5.x (#1568)

* Now compiling in a separate directory using truffle 5.

* Ported to 0.5.1, now compiling using 0.5.1.

* test now also compiles using the truffle 5 hack.

* Downgraded to 0.5.0.

* Sorted scripts.

* Cleaned up the compile script a bit.

scripts/build.sh

@@ -16,7 +16,7 @@ do
 done < contracts/.npmignore
 
 # Compile everything else.
-node_modules/.bin/truffle compile
+npm run compile
 
 # Return ignored files to their place.
 mv "$tmp_dir/"* contracts/

scripts/compile.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+
+# Configure to exit script as soon as a command fails.
+set -o errexit
+
+SOLC_05_DIR=solc-0.5
+
+# Delete any previous build artifacts
+rm -rf build/
+
+# Create a subproject where 0.5.x compilation will take place
+mkdir -p "$SOLC_05_DIR"
+
+cd "$SOLC_05_DIR"
+npm init --yes
+npm install --save-dev truffle@5.0.0
+
+rm -rf contracts
+ln --symbolic ../contracts contracts
+
+# Delete any previous build artifacts
+rm -rf build/
+
+# Compile
+echo "
+module.exports = {
+  compilers: {
+    solc: {
+      version: \"0.5.0\",
+    },
+  },
+};
+" > truffle-config.js
+
+npx truffle compile
+
+# Modify the paths in the artifacts to make it look as if they were built in the root
+sed --in-place --expression "s/\/$SOLC_05_DIR//g" build/contracts/*.json
+
+# Copy them back into the root
+cd ..
+cp --recursive "$SOLC_05_DIR"/build build