This lets SConstruct set things like USE_MYSQL
based on the host w/o complaining.
build/build_options/ALPHA_FS_TL:
build/build_options/ALPHA_FS:
build/build_options/ALPHA_SE:
Get rid of non-essential default-valued options.
--HG--
extra : convert_revision : 96308897d2b9269dbefffa6d50ac491379444030
build/SConstruct:
Move options file from <build_dir>/build_options to build_options/<build_dir>.
--HG--
extra : convert_revision : 0363f79ef5c9c157d9018fcae9c5e055e38e552d