Make ruby compatible with vscode plugin

[BugDiver]

Ref https://github.com/getgauge/gauge-vscode/issues/85

[BugDiver]

Dev-Notes

Gauge LSP runs the language runner indefinitely, to update the language runner with the latest changeset it needs to reload the file.

• populate step-cache with static parsed files instead of requiring it.
• store step implementations range (start line an end line).
• clear the step-cache and populate it by requiring implementations files only when execution starts (in the ExectionStarting request ).
• process StepPositionRequest to provide all step locations in a given file.