Fixes 2 issues while adding amazon-fireos platform after fresh cordova install.
1. create.js updated to create "libs" folder before copying it to the project's platform folder.
2. check_reqs.js updated to report error and abort if awv_interface.jar is missing from libs folder.
[CB-6392]Addig amazon-fireos platform fails with not so good error reporting
Fixes 2 issues while adding amazon-fireos platform after fresh cordova install.
1. create.js updated to create "libs" folder before copying it to the project's platform folder. Also, checking for awv_interface.jar existance is moved to create_project().
2. check_reqs.js no longer checks for awv_interface.jar.
Added amazon xmlns to project's template AndroidManifest.xml.
Updated log statement - android=>amazon-fireos.
Updated cordova.js after upleveling cordova-js from android port.
Add JavaDoc for CordovaResourceApi
defaults.xml: Add AndroidLaunchMode preference
CB-6543 Fix cordova/run failure when no custom_rules.xml available

Github: Close #99
CB-6491 add CONTRIBUTING.md
[CB-6636][amazon-fireos]Need to destroy webview properly
Added destroy() call in webview's handleDestroy() method.
[CB-6487]WebView not found in Chrome remote debugging

Enabling Chrome Devtools support for debug builds. It is disabled for release mode.