Use badge to show latest version in READMEs

[twyatt]

Used softwaremill/maven-badges as it provided a badge without the v prefix (shields.io had a v prefix and could be confusing for users).

Comparison

shields.io	softwaremill/maven-badges

README.md

[codecov]

Codecov Report

Merging #48 into develop will increase coverage by 0.14%.
The diff coverage is n/a.

@@              Coverage Diff              @@
##             develop      #48      +/-   ##
=============================================
+ Coverage      18.87%   19.01%   +0.14%     
  Complexity        17       17              
=============================================
  Files             17       15       -2     
  Lines            514      510       -4     
  Branches          50       49       -1     
=============================================
  Hits              97       97              
+ Misses           406      402       -4     
  Partials          11       11              

Impacted Files	Coverage Δ	Complexity Δ
core/src/main/java/android/BluetoothDevice.kt
core/src/main/java/Gatt.kt
core/src/main/java/Device.kt
processor/src/main/java/GattProcessor.kt	0.00% <0.00%> (ø)	0.00% <0.00%> (?%)