15 Feb 2019, 2n rel: bugfixing & project machinery

Changes

• SUPPORT also MATLAB >= R2016b(9.1.x), instead of >= R2018a(9.4.x );
  managed to encode POST body-params without relying on QueryParam.
• FIX: do not ignore MWClient.DefaultApiParams, but add them into URI.
• fix: clean up cookies before MWClient.login(), so repeated calls possible.
• fix: do not override given HttpOptions in HttpSession constructor - now
  possible to debug http-requests and save their Payload in MwClient.History.
• enh: MWClient accepts HttpSession on construction.
• Chore & docs enhancements:
  • add MWClient.Version constant to discover project release on runtime.
  • add .gitignore and this changelog.
  • some function docs improved.