Use gcc crate instead of homegrown hack

[polachok]

No description provided.

[mrmonday]

Hi there!

Thank you for your work. A couple of points:

• Could you use spaces instead of tabs please?
• This change removes the -Dstatic= -Dinline= hack, which means that the symbols are not exported, so linking will fail

Unrelatedly, we should really get Travis set up so this gets tested automatically.

[polachok]

I pushed an update and added a little test to see if it links.

[polachok]

I'll create a PR for travis when this one is merged (see https://github.com/polachok/netmap_sys/pull/2/files)

[mrmonday]

I'd actually really appreciate it if you could make the pull request for Travis now, since you've done the work! It would mean that this one can be tested properly before merging, which would be great.

Before you do that, could you add:

cache:
    directories:
        - $HOME/.cargo
rust:
    - stable
    - beta
    - nightly
notifications:
    irc:
        channels:
            - "chat.freenode.net#libpnet"
        use_notice: true

In there? Thanks!

[mrmonday]

Great work, thanks!