* started python API reference guide
* Added test to the API reference guide
* Added Price break
* added context variables to the build section
* Cleand up build section and added new example
* Fine tuning
* fixed picture
* removed unfinished python reference guide
* Added allocated_stock to the build rreport
* Added contect variables for user model
* Added link to user in build.md
* Fixed misunderstanding of can_complete
* Added context variables for Suppliers
* Fixed typos
* Added example for a warehouse pick list
* Added path trick to the picklist example
* Corrected typo
* Added context variables for stock locations
* changed some wordings
* Added a remark for get_setting
* Added example on int validator
* Added panel plugin example
* fixed typos
* Added button examples
* Formatting
* Fixed typos
