OPTICKS-1594:Prevent a crash in the LAS importer ImportOptionsDialog tab.

git-svn-id: svn://svn.code.sf.net/p/opticks/code/trunk/future@18688 6d0fddd1-9640-0410-91f9-aa98d5e64d34
OPTICKS-1595:Fix ehs link problem on RHEL

git-svn-id: svn://svn.code.sf.net/p/opticks/code/trunk/future@18689 6d0fddd1-9640-0410-91f9-aa98d5e64d34
Added .gitignore files to match svnignore properties