update most deps, notably including reqwest

Fixes #60

The reqwest dependency is significant because the old version required
an old version of openssl, complicating compilation on newer platforms.
reqwest also pulled in old/duplicate versions of hyper, tokio, etc.
Nice to drop a lot of that cruft.

I left rusqlite and uuid alone because they had breaking changes I
didn't want to mess with at the moment.

Bumped the minimum Rust version to 1.30.0, as required by the
new encoding_rs crate (and perhaps other things).

src/mp4.rs

@@ -1456,7 +1456,7 @@ impl FileInner {
         let start = s.s.sample_file_range().start + r.start;
         let mmap = Box::new(unsafe {
             memmap::MmapOptions::new()
-                .offset(start as usize)
+                .offset(start)
                 .len((r.end - r.start) as usize)
                 .map(&f)?
             });
@@ -2204,6 +2204,7 @@ mod bench {
     use db::testutil::{self, TestDb};
     use futures::{Future, future};
     use hyper;
+    use http::header;
     use http_serve;
     use self::test::Bencher;
     use std::error::Error as StdError;
@@ -2298,10 +2299,9 @@ mod bench {
         b.bytes = p;
         let client = reqwest::Client::new();
         let mut run = || {
-            use self::reqwest::header::{Range, ByteRangeSpec};
             let mut resp =
                 client.get(server.url.clone())
-                      .header(Range::Bytes(vec![ByteRangeSpec::FromTo(0, p - 1)]))
+                      .header(header::RANGE, format!("bytes=0-{}", p - 1))
                       .send()
                       .unwrap();
             buf.clear();

src/web.rs

@@ -621,7 +621,7 @@ mod bench {
         let client = reqwest::Client::new();
         let mut f = || {
             let mut resp = client.get(url.clone()).send().unwrap();
-            assert_eq!(resp.status(), reqwest::StatusCode::Ok);
+            assert_eq!(resp.status(), reqwest::StatusCode::OK);
             buf.clear();
             use std::io::Read;
             resp.read_to_end(&mut buf).unwrap();