Add in the files needed to build libcurl shared images on VMS.

Update the packages/vms/readme file to be current.

Also some files for the GNV based build were either missing or needed an
update.

curl_crtl_init.c is a special file that is run before main() to
set up the proper C runtime behavior.

generate_vax_transfer.com generates the VAX transfer vector modules from
the gnv_libcurl_symbols.opt file.

gnv_conftest.c_first is a helper file needed for configure scripts to
come up with the expected answers on VMS.

gnv_libcurl_symbols.opt is the public symbols for the libcurl shared
image.

gnv_link_curl.com builds the shared libcurl image and rebuilds other
programs to use it.

macro32_exactcase.patch is a hack to make a local copy of the VMS Macro32
assembler case sensitive, which is needed to build the VAX transfer modules.

report_openssl_version.c is a tool for help verify that the libcurl
shared image is being built for a minium version of openssl.
packages/vms/Makefile.am: add latest file additions to EXTRA_DIST