Support for pyramid-excel

pyramid use zope.alchemy and transaction which will do commit after each handler and does not want custom library to do database commit. hence, I am provide the option to disable commit if requested for sqlbook.py

Bug fixes

1. Bug fixes in django and sqlalchemy side: #1
2. Bug fix in django side only: #2
3. Pass on file type to reader and writers, due to pyexcel-text had one writer across many file types.

Indepence from pyexcel

• handle the delegate file interface to access various excel file formats
• support read and write access to csv, csvz, django models and sqlalchemy tables
• empower pyexcel-xls, pyexcel-xlsx, pyexcel-ods(3) as standalone library to read and write more formats

Optimization for loading single sheet from a multiple book

• Loads only one sheet from a multiple sheet book
• Use New BSD License

Abstraction - Prevent developer from providing incomplete functions

• Programmatically guide pyexcel extension developers on what methods should have been implemented.
  • It wont allow you to instantiate from you custom class unless you implement all abstract methods
• Passing custom keywords to your classes
• Providing NamedContent as a helper class for data content that does not have a name but a name(sheet name) is required when writing a pyexcel extension.

initial release

• the implementation of this package can be a plugin to pyexcel
• And can also be an indenpendent read/write library for any file format in mind