Pull request #704: CAS-13935
Merge in CASA/casa6 from CAS-13935 to master
* commit 'cd0a0d2382fcd4208c69410d8290b5dd69ff4394':
Cleaned up table of contents for README.md
Update Readme to include how to use sparse_check
Update path type to checkout files that are real in unittest directory
Fix error in reading datapaths. Print Help on empty arguments
Update to Sparse Check to include non unittest dirs. Added simple test cases
Update checking names of requested data directly
Add Error Handling if Data file cannot be found
Update to check for explicit path prior to checking real path
Add v1 of sparse checkout to casatestutils
