fix: update xud version on every compile

This ensures that the version displayed by xud on `GetInfo` calls is
updated every time it is compiled, to ensure that the version matches
the code that is running. Previously the version was only updated on
installation via npm.

Fixes #1449.

Author: sangaman

Diff for: package.json

@@ -13,8 +13,8 @@
     "config": "gulp config.create",
     "postinstall": "npm run precompile",
     "precompile": "node parseGitCommit.js",
-    "compile": "tsc && cross-os postcompile",
-    "compile:dev": "tsc --incremental --tsBuildInfoFile ./dist/.tsbuildinfo && cross-os postcompile",
+    "compile": "npm run precompile && tsc && cross-os postcompile",
+    "compile:dev": "npm run precompile && tsc --incremental --tsBuildInfoFile ./dist/.tsbuildinfo && cross-os postcompile",
     "compile:seedutil": "(cd seedutil && export PATH=\"$PWD/go/bin:$PATH\" && GOPATH=$PWD/go GO111MODULE=on go build -v)",
     "compile:watch": "tsc -w",
     "dev": "npm run compile:dev && npm start",