Add extra version variable and get method

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Add SpecFile.set_extra_version() draft

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Add basic test for set_extra_version()

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Add methods for getting full release string and release number

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Add method for setting release number

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Add methods for redefining Release with macro, and revert method

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Change release number in test.spec for testing purposes

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Use .format() for string instead of concatenation

Signed-off-by: Tomas Hozza <thozza@redhat.com>
SpecFile: improve some doc texts

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Change the Release when setting extra_version

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Use and set extra version SPEC file

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Fix determination of extra version in constructor

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Source0 may not include the '0' in name

Signed-off-by: Tomas Hozza <thozza@redhat.com>