osc-sdk-c v0.5.0

• update API
• reduce lines of code per calls
• enable usage of none and basic(login/password) auth method
• add osc_set_cfg_path to specify a configuration path.
• add OSC_ENV_FREE_AK / OSC_ENV_FREE_SK to have more fine grain control over what's free. (instead of just OSC_ENV_FREE_AK_SK)
• add osc_init_sdk_ext that take an argument that can be used to force some ak/sk and auth method