week.statistics now a date range
refactor time_maching calculations
stats method not equired in CLI
adding time zone to config
add task dirty_statistics
adding scopes and methods to period_statistic
better name for task
adding base for affluence trends
adding indexes
moving methods from model week to period
fix mean_diff calculation
refactoring the statistic calculator
Merge pull request #4 from themi/develop

Develop