Add CLI for offline instrumentation

[shanshin]

In the case of using third-party build systems (other than Gradle) for offline instrumentation of class-files, there is a need for a CLI wrapper over the Kover tool.

Offline instrumentation is necessary to collect coverage on another device, and then transfer the raw report to the machine where the instrumentation was performed to generate an HTMl or XML report.

As part of this task, it is necessary:

• introduce Kover artifacts for CLI capabilities
• create sh/bat scripts for invoking offline instrumentation and generating reports (optional)
• add documentation describing how to perform offline instrumentation

[shanshin]

Related PR: JetBrains/intellij-coverage#55

[shanshin]

Implemented in 0.7.0-Beta

[shanshin]

To collect coverage and generate a report, follow these steps:

1. download Kover CLI
2. instrument compiled classes by command like java -jar kover-cli-0.7.0-Beta.jar instrument path/to/classes --dest path/to/instrumented. See the details in the readme file
3. download Kover offline runtime with dependencies for the instrumented code
4. add kover-offline-runtime-0.7.0-Beta.jar archive to the application classpath
5. launch the application by passing the kover.offline.report.path system property, for example, through command-line startup arguments -Dkover.offline.report.path=path/to/binary/report. A binary coverage report will be written to the specified file.
6. generate a report by command like java -jar kover-cli-0.7.0-Beta.jar path/to/binary/report --classfiles path/to/classes --src /path/to/sources --html /path/to/html/report. See the details in the readme file

An example of using the CLI in Gradle is given in the readme.