Add missing tree.h on windows and use STATIC_EXPORT in bitvector

Both changes are required for making julia.h usable under MSVC
Add a specific error message for PCRE conflicts

When a different PCRE library is loaded than that which the stdlib
was compiled against, the compiled regular expressions may fail.
This compares the version strings of the compiled and loaded libpcre
and if different aborts (similar to how Julia will abort with BLAS error)
Fix sparse matrix printing.
Faster sparse kron. Fix #4958
sparse kron tests.
document apply, fixes #4961

bikeshed performance tip on column-major ordering
Merge pull request #4954 from tknopp/includeTreeH

Add missing tree.h on windows and use STATIC_EXPORT in bit vector (see #4937)
Use @inbounds in sparse kron.
Merge pull request #4959 from mbauman/pcre_error_message

Add a specific error message for PCRE conflicts
Add sparse kron improvements to NEWS.