Added membug to requirements.txt
Added some debugs for ShotServer
Added debugs to do_POST()
Added flow markers to tests/test_flow.py
README.md: info about submodules
Review fixes
Merge pull request #127 from mdevaev/test-flow-debug

Test-flow debug
Merge pull request #118 from mdevaev/req-membug

Added membug to requirements.txt