removed functions to generate the contents of rpm spec, .repo file and mock.cfg files as these are migrated into myrepo.repo
implemented (moved) a function to generate RPM SPEC and src.rpm packaged yum repo metadata files
fixed a syntax error in the RPM SPEC template; it seems that enclosing double quotes are not required for the string assigned to variables in RPM SPEC files
update an example of compiled template of RPM SPEC
added test cases for myrepo.repo.{gen_rpmspec,build_repodata_srpm}