Renamed "Run Command" to "Run Shell Command"

The original name is quite confusing for users, because they usually want to run Batch scripts inside this installer. "Execute Batch Command" is available inside "extra-tool-installers" plugin, so there's no need to implement such installer inside the core.

Related to: https://issues.jenkins-ci.org/browse/JENKINS-20635



Signed-off-by: Oleg Nenashev <nenashev@synopsys.com>