v0.3.4: Set up Vim plugin, Implemant no conversation mode

[docs] version info, Quick Start, Vim plugin setting
[feat] call kwargs GPT, GPTWindow
[feat] call keyword args
[fix] system prompt
[fix] argumentf for GPT()
[style] use gpt-3.5-turbo as default
Merge tag 'v0.3.3' into develop