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>
[JENKINS-21202] - Generalization of Command installers
This change adds an AbstractCommandInstaller, which can be extended for every script-based installation command.

Related to https://issues.jenkins-ci.org/browse/JENKINS-21202

Signed-off-by: Oleg Nenashev <nenashev@synopsys.com>
[FIXED JENKINS-21202] - Added a BatchCommandInstaller

Related to https://issues.jenkins-ci.org/browse/JENKINS-21202

Signed-off-by: Oleg Nenashev <nenashev@synopsys.com>
Fix failed to start when removed

When jenkins and daemon are removed and not purged,
failed to start.
Because `(echo && exit 0)` exits sub-shell only.
[FIXED JENKINS-21386] Allow more specific loggers to reduce log level
[FIXED JENKINS-21386] Allow reordering loggers, use first with matching name.
[JENKINS-16417]

My recommended fix in response to https://github.com/jenkinsci/jenkins/pull/1093. This does not eliminate nor exclude the need for more generic pluggability, but it would at least address the security concern.
Merge pull request #1086 from znz/master

Fix failed to start when removed
Merge pull request #1090 from daniel-beck/JENKINS-21386

[FIXED JENKINS-21386] Allow more specific loggers to reduce log level
Merge branch 'pull-1091'

Conflicts:
	core/src/main/java/hudson/logging/LogRecorder.java
	core/src/test/java/hudson/logging/LogRecorderTest.java
added a hook for use cases like https://github.com/jenkinsci/jenkins/pull/1079
Merge pull request #1078 from synopsys-arc-oss/run-shell-command_renaming

Renamed "Run Command" to "Run Shell Command"
[FIXED JENKINS-12231] ensure right owner
Revert "Merge branch 'pull-1091'"

This reverts commit 1fda95b6aea55cb216074b18bbb34fd8708c64c0, reversing
changes made to 0fd39c445a7a3e58ea9ae5ce605e6b01201b4d07.

Daniel Beck confirmed that I wasn't supposed to merge both 1090 and
1091. After discussion with him, I'm taking 1090.

See: https://github.com/jenkinsci/jenkins/commit/1fda95b6aea55cb216074b18bbb34fd8708c64c0#commitcomment-5112285
[JENKINS-16417]

Follow up fix as pointed out by Daniel Beck.
[maven-release-plugin] prepare for next development iteration
updated changelog for release
use <st:nbsp/>
updated changelog as a part of the release
merged back the RC branch