Add build script to compile .gresource files

Also add the required xml file and .gitignore rule.

.gitignore

@@ -1,3 +1,4 @@
 target
 *~
+*.gresource
 

Cargo.toml

@@ -4,6 +4,7 @@ authors = ["Jonas Platte <mail@jonasplatte.de>"]
 license = "GPL-3.0+"
 version = "0.1.0"
 repository = "https://github.com/fest-im/fest"
+build = "build/build.rs"
 
 [dependencies]
 futures = "0.1.17"

build/build.rs

@@ -0,0 +1,17 @@
+use std::process::Command;
+
+fn main() {
+    let gen_gresource = |file_prefix, dir| {
+        let fname = [file_prefix, "gresource.xml"].join(".");
+        let emsg = format!("Compiling {}/{}.gresource.xml failed.", dir, fname);
+        Command::new("glib-compile-resources")
+            .arg(fname)
+            .current_dir(dir)
+            .status()
+            .expect(&emsg);
+    };
+
+    gen_gresource("fest", "res");
+    gen_gresource("icons", "res/icons/hicolor");
+}
+

res/fest.gresource.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<gresources>
+  <gresource prefix="/org/fest-im/fest">
+    <file>main_window.glade</file>
+    <file>gtk/menus.ui</file>
+  </gresource>
+</gresources>
+