Structure test case descriptions

Structure test case descriptions

This commit structures the test case descriptions.

The file index.rst lists the subsequent chapters.
01-introduction.rst contains an overview of the project and deliverables.
02-methodology.rst describes the methodology for the generic test cases.
03-list-of-tcs.rst contains a list of merged generic test cases and a
sub-chapter for the feature test cases.
Glossary extracts definitions and abbreviations.

TC001, TC002, TC008, TC009, TC010, TC012 were adapted to work for pdf.
Template testcase_description_v2_template.rst was adapted to work for pdf.

Change-Id: Ia11e27e5d508f1a784e2a412b50739e32b13797f
Signed-off-by: Ana C <ana.cunha@ericsson.com>
(cherry picked from commit 00296cd85133d4f38a510e7ad3ecb0ff3fe4d56c)