Migrates build system from rake/paver to rake/invoke

- Adds deprecated decorator for pavement tasks
- Adds i18n tasks to invoke
- Adds utils, update paver prerequisites
- Migrates asset compilation and prereq installation to invoke
- Adds the inovke.txt requirements file to automatically install invoke
when calling a deprecated task through paver
- Migrates servers to invoke.
- Deprecates paver server tasks
- Adds docs tasks to invoke
- Removes paver dependencies of invoke tasks
- Adds pylint tasks to invoke
Currently fixing i18n tasks.
More fixing i18n
Cleaning up i18n.