duplicate free: axis2_repos_listener and axis2_dep_engine when module load failed

When the loading of a module failes (a dll not found, axis2.xml not correct, etc) the engine and configuration are directly freed.
This results in duplicate free.
Ususally, this is not really a problem, as all ptrs in the structs that are freed twice are NULL, resulting in no additional problems.
Still, with MSVC and _CRTDBG_MAP_ALLOC, this leads to crashes.

Stack trace summary:
1) failed dep_engine_load_client calls repos_listener_free
2) failed dep_engine_load_client calls conf_free which calls dep_engine_free
3) which calls repos_listener_free (again)
4) failed axis2_build_client_conf_ctx calls dep_engine_free (again).

Problem seems to be that the ownership is not agreed on between conf->dep_engine and dep_engine->conf.

complete stack traces:
> axis2_engine.dll!axis2_repos_listener_free(axis2_repos_listener * repos_listener=0x03141920, const axutil_env * env=0x0312f3e0) Line 149 C
axis2_engine.dll!axis2_dep_engine_load_client(axis2_dep_engine * dep_engine=0x03130510, const axutil_env * env=0x0312f3e0, const char * client_home=0x0312e144) Line 964 C
axis2_engine.dll!axis2_build_client_conf_ctx(const axutil_env * env=0x0312f3e0, const char * axis2_home=0x0312e144) Line 222 + 0x8 bytes C
axis2_engine.dll!axis2_svc_client_create_with_conf_ctx_and_svc(const axutil_env * env=0x0312f3e0, const char * client_home=0x0312e144, axis2_conf_ctx * conf_ctx=0x00000000, axis2_svc * svc=0x00000000) Line 174 + 0x1b bytes C
axis2_engine.dll!axis2_svc_client_create(const axutil_env * env=0x0312f3e0, const char * client_home=0x0312e144) Line 126 C
axis2_engine.dll!axis2_stub_create_with_endpoint_ref_and_client_home(const axutil_env * env=0x0312f3e0, axis2_endpoint_ref * endpoint_ref=0x0312f418, const char * client_home=0x0312e144) Line 66 + 0xb bytes C

> axis2_engine.dll!axis2_dep_engine_free(axis2_dep_engine * dep_engine=0x03130510, const axutil_env * env=0x0312f3e0) Line 386 C
axis2_engine.dll!axis2_conf_free(axis2_conf * conf=0x00000000, const axutil_env * env=0x0312f3e0) Line 357 C
axis2_engine.dll!axis2_dep_engine_load_client(axis2_dep_engine * dep_engine=0x03130510, const axutil_env * env=0x0312f3e0, const char * client_home=0x0312e144) Line 965 C
axis2_engine.dll!axis2_build_client_conf_ctx(const axutil_env * env=0x0312f3e0, const char * axis2_home=0x0312e144) Line 222 + 0x8 bytes C
axis2_engine.dll!axis2_svc_client_create_with_conf_ctx_and_svc(const axutil_env * env=0x0312f3e0, const char * client_home=0x0312e144, axis2_conf_ctx * conf_ctx=0x00000000, axis2_svc * svc=0x00000000) Line 174 + 0x1b bytes C
axis2_engine.dll!axis2_svc_client_create(const axutil_env * env=0x0312f3e0, const char * client_home=0x0312e144) Line 126 C
axis2_engine.dll!axis2_stub_create_with_endpoint_ref_and_client_home(const axutil_env * env=0x0312f3e0, axis2_endpoint_ref * endpoint_ref=0x0312f418, const char * client_home=0x0312e144) Line 66 + 0xb bytes C

> axis2_engine.dll!axis2_repos_listener_free(axis2_repos_listener * repos_listener=0x03141920, const axutil_env * env=0x0312f3e0) Line 149 C
axis2_engine.dll!axis2_dep_engine_free(axis2_dep_engine * dep_engine=0x03130510, const axutil_env * env=0x0312f3e0) Line 570 C
axis2_engine.dll!axis2_conf_free(axis2_conf * conf=0x00000000, const axutil_env * env=0x0312f3e0) Line 357 C
axis2_engine.dll!axis2_dep_engine_load_client(axis2_dep_engine * dep_engine=0x03130510, const axutil_env * env=0x0312f3e0, const char * client_home=0x0312e144) Line 965 C
axis2_engine.dll!axis2_build_client_conf_ctx(const axutil_env * env=0x0312f3e0, const char * axis2_home=0x0312e144) Line 222 + 0x8 bytes C
axis2_engine.dll!axis2_svc_client_create_with_conf_ctx_and_svc(const axutil_env * env=0x0312f3e0, const char * client_home=0x0312e144, axis2_conf_ctx * conf_ctx=0x00000000, axis2_svc * svc=0x00000000) Line 174 + 0x1b bytes C
axis2_engine.dll!axis2_svc_client_create(const axutil_env * env=0x0312f3e0, const char * client_home=0x0312e144) Line 126 C
axis2_engine.dll!axis2_stub_create_with_endpoint_ref_and_client_home(const axutil_env * env=0x0312f3e0, axis2_endpoint_ref * endpoint_ref=0x0312f418, const char * client_home=0x0312e144) Line 66 + 0xb bytes C

> axis2_engine.dll!axis2_dep_engine_free(axis2_dep_engine * dep_engine=0x03130510, const axutil_env * env=0x0312f3e0) Line 386 C
axis2_engine.dll!axis2_build_client_conf_ctx(const axutil_env * env=0x0312f3e0, const char * axis2_home=0x0312e144) Line 228 + 0x7 bytes C
axis2_engine.dll!axis2_svc_client_create_with_conf_ctx_and_svc(const axutil_env * env=0x0312f3e0, const char * client_home=0x0312e144, axis2_conf_ctx * conf_ctx=0x00000000, axis2_svc * svc=0x00000000) Line 174 + 0x1b bytes C
axis2_engine.dll!axis2_svc_client_create(const axutil_env * env=0x0312f3e0, const char * client_home=0x0312e144) Line 126 C
axis2_engine.dll!axis2_stub_create_with_endpoint_ref_and_client_home(const axutil_env * env=0x0312f3e0, axis2_endpoint_ref * endpoint_ref=0x0312f418, const char * client_home=0x0312e144) Line 66 + 0xb bytes C