Second release candidate

features

• Access directly with B2SAFE credentials #83
• Upgrade an existing installation #87
• B2safe based accounting for all endpoints #88
• Different response when calling /auth/askauth not from a browser #92
• Certificates folder name b2access #94
• Python client template #95
• Using curl option -u to pass b2safe credentials #97
• Update documentation for authentication via b2safe credentials #98
• New bugs #96
• Other minor changes and/or small improvements