added system util functions
updated fcgi cli implementation
removed unused module `wsgiservers`
added support for session params in custom `sesssion_maker`
removed `level` parameter from fcgi module
renamed `prepare_dirs` -> `safe_makedirs`
using waitpid when stopping fcgi process
Merge pull request #100 from riffm/fcgi-cli-update

Fcgi cli update
modifying a copy of `session_params` when setting default `autoflush` value
Merge pull request #101 from riffm/sqla-tools

added sqla tools to gently recreate schema
Merge pull request #102 from riffm/session_maker-update

added support for session params in custom `sesssion_maker`