Update coalition.md to include King County (#28)

Author: safrazier17

docs/coalition.md

@@ -3,6 +3,7 @@
 - [California Integrated Travel Project (Cal-ITP)](https://www.calitp.org/)
 - [Denver Regional Transportation District (RTD)](https://www.rtd-denver.com/)
 - [ENTUR](https://entur.no/)
+- [King County, Washington](https://kingcounty.gov/)
 - [Los Angeles County Metropolitan Transportation Authority (Metro)](https://www.metro.net/)
 - [Massachusetts Bay Transportation Authority (MBTA)](https://www.mbta.com/)
 - [Metro Transit (Minnesota)](https://www.metrotransit.org/home)

docs/cosignatories.md

@@ -32,6 +32,7 @@
 - [Interline](https://interline.io)
 - [Ito World](https://www.itoworld.com/)
 - [Jarvus Innovations](https://jarv.us/)
+- [King County, Washington](https://kingcounty.gov/)
 - [Kuba](https://www.kubapay.com/)
 - Albert Kochaphum, Individual
 - [Littlepay](https://littlepay.com/)

docs/img/KClogo_v_wbox_blackbg(1).jpg

@@ -12,11 +12,14 @@
     <img src="img/entur.png" alt="ENTUR" />
   </div>
   <div class="logo-grid__item">
-    <img src="img/mbta.png" alt="Massachusetts Bay Transportation Authority (MBTA)" />
+    <img src="img/king-county-wa.jpg" alt="King County, Washington" />
   </div>
   <div class="logo-grid__item">
     <img src="img/metro.png" alt="Los Angeles County Metropolitan Transportation Authority" />
   </div>
+  <div class="logo-grid__item">
+    <img src="img/mbta.png" alt="Massachusetts Bay Transportation Authority (MBTA)" />
+  </div>
   <div class="logo-grid__item">
     <img src="img/metrotransit.png" alt="MetroTransit" />
   </div>