Added doc

MANIFEST.in

@@ -8,3 +8,4 @@ include *.xml
 include *.odt
 include *.csv
 include tests/*
+include doc/*

doc/index.rst

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+Party Module
+############
+
+The party module defines the concepts of party, category and contact
+mechanism. It also comes with reports to print labels and letters and
+a *Check VIES* wizard.
+
+
+Party
+*****
+
+A party can be a person, a company or any organisation that one want
+to consider as the same entity. A party is defined by a name, a code,
+a language, a VAT code, categories, contact mechanisms and a list of
+addresses.
+
+Two reports are available:
+
+- The *Labels* report creates a document with the names and addresses
+  of all selected parties which are preformatted to be printed on
+  labels that can be stuck on an envelope.
+- The *Letter* report create a document pre-filled with the company
+  header, the address of the recipient, a date, a greeting, an ending
+  and the signature of the current reader.
+
+The *Check VIES* wizard allow to check the VAT number of parties with
+the VIES web service.
+
+
+Address
+*******
+
+An address is made of a name, a street, a zip number, a city, a
+country, a subdivision. A sequence allow to order them.
+
+
+Contact Mechanism
+*****************
+
+A contact mechanism is made of a type, value and comment. Type can be
+*Phone*, *Mobile*, *Fax*, *E-Mail*, *Website*, *Skype*, *SIP*, *IRC*,
+*Jabber* or *Other*.
+
+
+Category
+********
+
+A Category is just composed of a name, thus constituting tags that can
+be associated to parties. Categories are organised in a tree structure.