* reduce to a few, supported functions.
* change all functions to take the debug level as parameter.
* use symbolic names for the debug levels.
* fix tools to pass "verbose"/"opt_debug" as ctx->debug.
git-svn-id: https://www.opensc-project.org/svnp/opensc/trunk@4118 c6295689-39f2-0310-b995-f0e70906c6a9