Update README.md

CSS for vector based country flags. See the

[demo](http://lipis.github.io/flag-icon-css/).

CSS classes

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`.flag-icon` sets the correct proportions for the flag icon when used inline

with text.

`.flag-icon-xx` sets the `background-image` with the correct flag, where `xx` is the

[ISO 3166-1-alpha-2 code](http://www.iso.org/iso/country_names_and_code_elements).

`.flag-icon-squared` for the squared version of the flag.

`.flag-icon-background` sets the the background to `position: 50%`,

`repeat:no-repeat` and `size:contain`.

Usage

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For using the flags inline with text add the classes `.flag-icon` and `.flag-icon-xx`

to an empty `<span>`. If you want the flag to have the squared version then also add

the clas `flag-icon-squared`. Example:

(where `xx` is the

[ISO 3166-1-alpha-2 code](http://www.iso.org/iso/country_names_and_code_elements) 

of a country) to an empty `<span>`. If you want the flag to have the squared version 

then also add the class `flag-icon-squared`. Example:

    <span class="flag-icon flag-icon-gr"></span>

    <span class="flag-icon flag-icon-gr flag-icon-squared"></span>