Remove Bintray gradle files, add maven changes

[RHenigan]

Fixes #1662

This PR is ready for review.

Risk

This PR makes [no] API changes.

Testing Plan

• I have verified that I have not introduced new warnings in this PR (or explain why below)
• I have run the unit tests with this PR
• I have tested this PR against Core and verified behavior (if applicable, if not applicable, explain why below).
• I have tested Android, Java SE, and Java EE

Unit Tests

N/A

Core Tests

Smoke Test

Summary

This PR will remove the bintray gradle build scipts, add a gradle plugin to automate the release process to mavenCentral, and add new gradle.properties files for the pom.xml file generation and credentials

CLA

• I have signed the CLA

[codecov]

Codecov Report

Merging #1663 (ef3a42f) into develop (7551226) will decrease coverage by 0.01%.
The diff coverage is n/a.

❗ Current head ef3a42f differs from pull request most recent head 8e841df. Consider uploading reports for the commit 8e841df to get more accurate results

@@              Coverage Diff              @@
##             develop    #1663      +/-   ##
=============================================
- Coverage      54.01%   54.00%   -0.02%     
+ Complexity      5307     5303       -4     
=============================================
  Files            555      555              
  Lines          24532    24532              
  Branches        3094     3094              
=============================================
- Hits           13252    13248       -4     
- Misses         10131    10134       +3     
- Partials        1149     1150       +1     

Impacted Files	Coverage Δ	Complexity Δ
...nk/managers/audio/AudioDecoderCompatOperation.java	75.00% <0.00%> (-4.55%)	9.00% <0.00%> (-1.00%)
...com/smartdevicelink/util/MediaStreamingStatus.java	63.80% <0.00%> (-0.96%)	17.00% <0.00%> (ø%)
...ink/managers/screen/BaseTextAndGraphicManager.java	63.75% <0.00%> (-0.42%)	50.00% <0.00%> (-2.00%)