Merge branch '2.0.0'
Merge branch 'master' into 2.0.0
[application]modified hello world  demo
[cache]fixed a bug
[cache]optimized init flow
[core]removed debug code
[core]add docs
[core]added model validation
[core]fixed docs
[core]added currect response header
[core]fixed route bug
[core]fixed generate bug
[core]dynamic find module view
[core]todo widget
[database]add template space
[helper]fixed docs
[helper]added format tree