Matching Expressions
====================

Hotfixes can provide a `for` key with an array of supported systems. The
expressions are evaluated using Symfony's ExpressionLanguage and as such
can handle some pretty complex stuff.

For a hotfix to be considered supported, at least one of the expressions
must evaluate to true.


## Example:

    for:
        - lsb.id=='raspbian'
        - lsb.id=='ubuntu' and lsb.release=>'16.04'


## System facts

### Distribution

Information is retrieved using `lsb_release` or the `/etc/os-release` file.

      lsb.id            Distribution ID (ex. ubuntu or raspbian)
      lsb.description   Pretty description
      lsb.release       Version number (ex. 16.04 or 8)
      lsb.codename      Release codename (ex. xenial, not always present)