Testsuite: add a time.sleep(.2) in checking pane_current_path, use TE…

…ST_SESSION_PREFIX as default prefix in get_test_session_name/window_name.

Version 0.1.9, changes by @ThiefMaster tmux-python#73, tmux-python#76, …

…tmux-python#77.

Tag v0.1.8 of tmux with before_script support, fix from tmux-python#72 …

…for freeze

directories. Testsuite updates.

fix tmux-python#55. where tmuxp would crash with letter version Versi…

…on 0.1.7.

Fix tmux-python#49 package_metadata.py missing from MANIFEST.in

v0.1.4. Update changelog.