Merge pull request #1631 from pentaho-nbaker/5.1

[PDI-12413] Reverting SpringSecurityPrincipalProvider enhancements due t...
[BISERVER-11745] Editing a blockout does not preserve the duration
Merge pull request #1633 from mdamour1976/5.1

[BISERVER-11745] Editing a blockout does not preserve the duration
[PDI-12413] Adding default for singleTenantAdminUserName in case one is not supplied.
[BISERVER-11722] Roles with special characters do not retain their Operation Permissions
Merge pull request #1636 from pminutillo/5.1

[BISERVER-11722] Roles with special characters do not retain their Opera...
[PDI-12418] - removed execute perms for power user as execute permission lifecycle manager adds the perms for power user backport 5.1
Merge pull request #1639 from pentaho-skarmali/5.1

[PDI-12418] - removed execute perms for power user as execute permission...
[BISERVER-11751] - IE: Couldn't upload files in Browse perspective
Merge pull request #1641 from jeffreythomas/5.1-dev

5.1 dev
[BISERVER-11758] - adding users to roles was using incorrect util for generating the tenant id, causing the cache to keep the old user credentials.  Also, removing users from roles were not getting purged from the cache.  cherry-picked from ce700ed.
[MOBILE-484] Pentaho Mobile is now presenting the user with BasicAuth rather than the mobile login page
Merge pull request #1644 from kurtwalker/BISERVER-11758-51

Biserver 11758 51
Merge pull request #1645 from mdamour1976/5.1

[MOBILE-484] Pentaho Mobile is now presenting the user with BasicAuth rather than the mobile login page
[BISERVER-11761] Added JavaScript string encoding for SESSION_NAME and HOME_FOLDER in webcontext
Merge pull request #1647 from pminutillo/BISERVER-11761

Biserver 11761
[BISERVER-11770] Shutting-down existing scheduler properly so it's not orphaned in the JVM preventing JVM shutdown.