rust/shed/hostname: rename hostname dependency to unbreak doctests (#15)

Summary:
Pull Request resolved: https://github.com/facebookexperimental/rust-shed/pull/15

With the update from rustc 1.44 to 1.47 the doctests started to break when building a crate that depends on a different crate of the same name, see this: https://github.com/rust-lang/cargo/issues/6819

This diff also removes the TravisCI build as it was broken and unused for some time.

Reviewed By: krallin

Differential Revision: D24390815

fbshipit-source-id: fa9c78ef394640afbf8c419f8276bbf339960406

build/fbcode_builder/specs/rust_shed.py

-#!/usr/bin/env python
-# Copyright (c) Facebook, Inc. and its affiliates.
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-from __future__ import unicode_literals
-
-from shell_quoting import path_join
-import specs.fbthrift as fbthrift
-
-
-def fbcode_builder_spec(builder):
-    builder.enable_rust_toolchain()
-    return {
-        "depends_on": [fbthrift],
-        "steps": [
-            builder.set_env(
-                "THRIFT", path_join(builder.option("prefix"), "bin", "thrift1")
-            ),
-            builder.fb_github_cargo_build(
-                "rust-shed/", github_org="facebookexperimental"
-            ),
-        ],
-    }