CRM-14798 - CRM_Case_XMLRepository - Don't double-munge the case-type name.

Prior to this commit, the naming for a case-type flowed more or less
like:

1. User makes up a display-name (title/label)
2. That title is munged via CRM_Utils_String::titleToVar to produce a machine-name
3. That machine-name is munged via CRM_Case_XMLProcessor::mungeCaseType to produce a file-name

As we begin allowing more varied dataflows for managing CaseType XML files
and CaseType DB records, it becomes more important for the naming behavior
to intuitive.
CRM-14798 - crmCaseType - Filter/validate caseType.name

If the name is auto-generated, filter out invalid characters. If the name is
manually-generated, emphasize errors.
CRM-14798 - XMLRepository - Load XML files using the real type name *or* the double-munged name
CRM-14798 - CRM_Utils_Check - Display warning if site has mismatched file names
xml/configuration - Remove unused, duplciate CiviCase XML files

The same files are in "xml/configuration" and
"CRM/Case/xml/configuration.sample".  Of the two, only the latter is ever
used.

See also: discussion of https://github.com/civicrm/civicrm-core/pull/3581
Merge pull request #3581 from totten/master-casetype-name2

CRM-14798 - CaseType - Make "name" handling simpler and more intuitive