v0.8.5

• #297: Enchance subprocess interaction std[in|out|err]. Needed for interact with big buffer, fixes :issue:251, thank you @gil-obradors!
• #303: Add common.get_libtmux_version which gives the tmux version as a loose constraint. Fix linking to terms inside docs, and duplicate description of module which sphinx warned about in api.rst.
• #266: Fix issue on local tests where env variables would cause show-environment to pause tests indefinitely.