mediainfo 0.2.0

Rust bindings for libmediainfo
## About
This is a simple wrapper around the [MediaInfo](https://mediaarea.net/en/MediaInfo)
library using Rust types.

The entire libmediainfo API is not exposed yet. The reason is basically because I don't
have a test case for the rest of the API.

Some information about the MediaInfo API can be found
[here](https://mediaarea.net/en/MediaInfo/Support/SDK), but not a lot of information is
available. The *exemples* directory has some basic use of the API.

## Examples
The examples can be run with:

```
cargo run --example [example_name]
```

for example:

```
cargo run --example basic_info
```

## Documentation
Yet to come.

## Requiments
### Rust
We target the most recent stable version (currently "1.17"). The best way to get it is
via `rustup` (or some bleeding edge Linux distro).

### MediaInfo Library
In Linux you should install libmediainfo (probably found in your distro package manager).
For Arch Linux users:

```
 # pacman -S libmediainfo
```

On Linux Mint 18 (and probably others ditros that use `apt`):

```
 # apt-get install libmediainfo
```

* Note: `libmediaifo` depends on `libstdc++`, but for some reason it was not installed
by `apt` in my test. After installing it the linker (`ld`) was still unable to link to
`stdc++` and I had to manually create a symbolic link to
`/usr/lib/x86-64-linux-gnu/libstdc++.s0.6`.

The wrapper was written against the version "0.7.94" (current version on Arch
repository).

We also depend on ```libc``` but it should be a dependency of ```libmediainfo```.

### pkg-config
Currently the build "script" only supports building with ```pkg-config```.