Recommended update for rust

This update for rust, cargo fixes the following issues:

- bsc#1030232: Update rust to 1.24.0, cargo to 0.25.0

These versions are build dependencies for an upcoming update to Mozilla Firefox 60 RSR.

Fixed bugs
bnc#1030232
rust >= 1.24.0 and cargo >= 0.25 required for Firefox 60 ESR
Selected Binaries
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