Previously:
* On Unix, an -export-symbol-regex (g_)|(glib_) was used, and the .symbols
files were used in "make check"
* On Windows, the .symbols files are massaged into a format which MSVC
expects as an export list
Now:
* On both Unix and Windows, the .symbols file is used as the list of
symbols to export, and code to generate the exported list per
platform is unified. Even symbols starting with g_ are not exported
unless they are in the file. The abicheck.sh tools are deleted.
https://bugzilla.gnome.org/show_bug.cgi?id=688681
