- added pyproject.toml
- removed build and install wrappers
- simlifications and fixes

- it seems that install_requires is ignored when calling install.run
  from install wrapper. install.do_egg_install() should fix the problem

- added specialized class as git revision provider
- build step will also update version.py
- in absence of .git dir version and git_revision will be taken
  from package distribution

- removed tests_require from setup.py it is depreciated in favor of tox
- setup test env in tox
- removed gitpython dependency

- Setup will create version file with current version info

- Implemented comment body patching using diff_match_patch library to follow original hived node behavior
- extended string literal normalization/escaping to support unicode strings containing nonprintable characters

Fixed internal error during processing response containing a Decimal object (value of some Decimal SQL column)

Added git versioning to the build process