update readme

Signed-off-by: Guillaume W. Bres <[email protected]>

Author: gwbres

README.md

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 GNSS Quality Control Traits
 ===========================
 
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+
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+
 The Quality Control traits library (`gnss-qc-traits`) is a small library
 that offers the basic operations to form a geodesy processing pipeline, as used by
 our [Quality Control library](https://github.com/rtk-rs/gnss-qc).