TabularReader::__destruct() fix for lazy fclose()
comment fix for Reader and Writer
tweaked TabularWriter::__destruct()
typo fix for open() methods
modified TabularWriter comments
DelimitedReader::open() checks for fopen() failure
DelimitedWriter::open() checks for fopen() failure
FixedWidthReader::open() checks for fopen() failure
FixedWidthWriter::open() checks for fopen() failure
modified comments
refactored ArrayField.php
Field class renamed to ScalarField
fixed-width field values are fit to the allotted field width
refactored TabularReader::_get()
improved scalar field tests
TabularWriter::__destruct() fix for lazy fclose()
variable-length ArrayFields are no longer modified during reading/writing
modified tutorial.md
fixed DateTimeField::encode() for fixed-width null values
improved scalar field tests