#2349 Failing test for Moutain Lion !ColumnDataReader

git-svn-id: https://chaste.cs.ox.ac.uk/svn/chaste/trunk@19486 b5f69653-2bf5-0310-8201-b0dafb8e1405
#2349 Proper failing test for Moutain Lion !ColumnDataReader (r19486 passes)

git-svn-id: https://chaste.cs.ox.ac.uk/svn/chaste/trunk@19488 b5f69653-2bf5-0310-8201-b0dafb8e1405
#2349 Demonstrate reading with underflow on Gnu/Linux

git-svn-id: https://chaste.cs.ox.ac.uk/svn/chaste/trunk@19489 b5f69653-2bf5-0310-8201-b0dafb8e1405