Include <windows.h> explicitly, surrounded by the prewin.h and
postwin.h headers. Also #undef ERROR to avoid a clash. Approved by
caolan.

For some reason the indentations were all out of wrack.

Replaced use of std::vector being used as a c-style array, with
boost::ptr_vector to make the code simpler.  This change in fact
slightly improves import performance.

When starting from a fresh config, Calc failed to assign default 'Calc A1'
syntax unless the user specifically goes to the Options page and sets the
formula syntax in the Calc - Formula options page.  This caused e.g.
print range editing to fail miserably. (fdo#31041)