Add soname to libquiche.so

Using cdylib-link-lines, add soname to the generated shlibs.

It will add the following to libquiche.so:

```
% readelf -d target/debug/libquiche.so
...
 0x000000000000000e (SONAME)             Library soname: [libquiche.so.0]
```

For linux, *bsd, android, ios and macos.

Fixes #598
Fixes #165

quiche/Cargo.toml

@@ -57,6 +57,7 @@ features = ["boringssl-boring-crate", "qlog"]
 rustdoc-args = ["--cfg", "docsrs"]
 
 [build-dependencies]
+cdylib-link-lines = "0.1"
 cmake = "0.1"
 pkg-config = { version = "0.3", optional = true }
 

quiche/src/build.rs

@@ -277,4 +277,8 @@ fn main() {
     if cfg!(feature = "pkg-config-meta") {
         write_pkg_config();
     }
+
+    if target_os != "windows" {
+        cdylib_link_lines::metabuild();
+    }
 }