This is the first batch of fixes that should be easy to verify based on context.
This fixes problem numbers: 220 (ast), 323-324 (symtable),
321-322 (structseq), 215 (array), 210 (hotshot), 182 (codecs), 209 (etree).
longobject.c: also fix an ssize_t problem
<a> could have been NULL, so hoist the size calc to not use <a>.
_ssl.c: under fail: self is DECREF'd, but it would have been NULL.
_elementtree.c: delete self if there was an error.
_csv.c: I'm not sure if lineterminator could have been anything other than
a string. However, other string method calls are checked, so check this
one too.
cast first PyUnicode_Decode argument to proper type (why is
"char *" used for encoded byte streams, btw? shouldn't that
be "void *" or, if necessary, "unsigned char *"?)