cargo-rpm: Initial crate with "cargo rpm init" command

Adds a "cargo rpm" subcommand which builds RPM releases of Rust projects.

Well... not just yet, but "cargo rpm build" will do that, and this PR was
already getting pretty unwieldy.

In an act of inception, this project is already "cargo rpm init"-ed.

Cargo.toml

@@ -1,6 +1,7 @@
 [workspace]
 members = [
     "canonical-path",
+    "cargo-rpm",
     "iq-cli",
     "rpmlib",
     "rpmlib-sys",

cargo-rpm/.rpm/cargo-rpm.spec

@@ -0,0 +1,40 @@
+%define __spec_install_post %{nil}
+%define __os_install_post %{_dbpath}/brp-compress
+%define debug_package %{nil}
+
+Name: cargo-rpm
+Summary: Build RPMs from Rust projects using Cargo
+Version: @@VERSION@@ # Set automatically by "cargo rpm build"
+Release: 1
+License: ASL 2.0
+Group: Applications/System
+Source0: %{name}-%{version}.tar.gz
+URL: https://github.com/iqlusion-io/crates/
+
+BuildRoot: %{_tmppath}/%{name}-%{version}-%{release}-root
+
+%description
+%{summary}
+
+%prep
+%setup -q
+
+%build
+# Empty section.
+
+%install
+rm -rf %{buildroot}
+mkdir -p  %{buildroot}
+
+# in builddir
+cp -a * %{buildroot}
+
+%clean
+rm -rf %{buildroot}
+
+%files
+%defattr(-,root,root,-)
+%config(noreplace) %{_sysconfdir}/*
+${_bindir}/*
+%{_sbindir}/*
+

cargo-rpm/Cargo.toml

@@ -0,0 +1,25 @@
+[package]
+name        = "cargo-rpm"
+description = "Build RPMs from Rust projects using Cargo"
+version     = "0.0.0" # Also update html_root_url in lib.rs when bumping this
+authors     = ["Tony Arcieri <tony@iqlusion.io>"]
+license     = "Apache-2.0"
+homepage    = "https://github.com/iqlusion-io/crates/"
+repository  = "https://github.com/iqlusion-io/crates/tree/master/cargo-rpm"
+readme      = "README.md"
+categories  = ["command-line-utilities", "development-tools"]
+keywords    = ["rpm", "cargo", "package", "release"]
+
+[dependencies]
+failure = "0.1"
+gumdrop = "0.4"
+gumdrop_derive = "0.4"
+handlebars = "1.0.0-beta.1"
+iq-cli = { version = "0", path = "../iq-cli" }
+lazy_static = "1"
+serde = "1"
+serde_derive = "1"
+toml = "0.4"
+
+[package.metadata.rpm.target]
+cargo-rpm = { path = "/usr/bin/cargo-rpm" }