CRM-14798 - timelineTable.html - Allow blank statuses

The reference XML files include blank statuses, so XML files in the wild
probably have blanks, too.  We should be able to read/write real XML files.

Note that for *new* activities in the timeline, the default status is
"Scheduled".
CRM-14798 - crmCaseType/list.html - Fix enabled/disabled labels
CRM-14798 - crmCaseType/timelineTable.html - Use select2
CRM-14798 - crmCaseType/timelineTable.html - Incl new activities in dropdown
Merge pull request #3572 from totten/master-casetype-tweaks

CRM-14798 - crmCaseType - Misc tweaks