Added Astra support to README and RELEASE notes (#443)

README.md

@@ -64,6 +64,7 @@ Supported Cars
 | Acura                | RDX 2018                | AcuraWatch Plus      | Yes     | Yes            | 25mph<sup>1</sup>| 12mph          | Nidec             |
 | Chevrolet<sup>3</sup>| Malibu 2017             | Adaptive Cruise      | Yes     | Yes            | 0mph             | 7mph           | Custom<sup>7</sup>|
 | Chevrolet<sup>3</sup>| Volt 2017-18            | Adaptive Cruise      | Yes     | Yes            | 0mph             | 7mph           | Custom<sup>7</sup>|
+| Holden<sup>3</sup>   | Astra 2017              | Adaptive Cruise      | Yes     | Yes            | 0mph             | 7mph           | Custom<sup>7</sup>|
 | Honda                | Accord 2018             | All                  | Yes     | Stock          | 0mph             | 3mph           | Bosch             |
 | Honda                | Civic 2016-18           | Honda Sensing        | Yes     | Yes            | 0mph             | 12mph          | Nidec             |
 | Honda                | Civic 2017-18 *(Hatch)* | Honda Sensing        | Yes     | Stock          | 0mph             | 12mph          | Bosch             |

RELEASES.md

@@ -7,6 +7,7 @@ Version 0.5.6 (2018-11-16)
  * More tuning to Honda positive accelerations
  * Reduce brake pump use on Hondas
  * Chevrolet Malibu support thanks to tylergets!
+ * Holden Astra support thanks to AlexHill!
 
 Version 0.5.5 (2018-10-20)
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