Fixed a rare bug causing blank cigar strings on reads that are at the
end of a block and when ALLOW_UAC is not defined, to be interpreted as
EOF.

See patch https://sourceforge.net/p/staden/bugs/105/ and debian bug
report https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=736565


git-svn-id: svn://svn.code.sf.net/p/staden/code/io_lib@3608 ba6f2710-ca9f-427c-89d3-5bf716dbc8e1
Merging xx#minimal.sam bug fix accidentally applied to cram_refactor branch.


git-svn-id: svn://svn.code.sf.net/p/staden/code/io_lib@3609 ba6f2710-ca9f-427c-89d3-5bf716dbc8e1
Replaced a lot of hard coded data series variables with array indices.


git-svn-id: svn://svn.code.sf.net/p/staden/code/io_lib@3610 ba6f2710-ca9f-427c-89d3-5bf716dbc8e1