Update propal.class.php

it's this->lines who used on create propal function not this->products
add filter to effectif select
Uniformization and simplification of code.
Merge branch 'develop' of git@github.com:Dolibarr/dolibarr.git into develop
Fix typo
Qual: Removed useless method

The method is already in the DoliDB base class
Qual: Moved duplicate methods to base method
Fix undeclared variable
Clean corrupted data for categories
Qual: Moved duplicate method to base method
Experiment hidden option MAIN_MENU_INVERT
Add message on disconnect button when using an authentication mode where
disconnect has no sense.
Add table for email templates.
Removed deprecated table llx_domain.
New: Add option FACTURE_SENDBYEMAIL_FOR_ALL_STATUS to allow to send
invoice
by email whatever is its status.
Hide a column that is always 0.
Qual: Prevent potential JS injection
Fix : proposal validation was converting third as customer
Merge branch 'develop' of github.com:Dolibarr/dolibarr into develop
Qual: Better type check
Qual: Removed useless assignment from void method