All patching config files in memory

All patching config files in memory

It adds the yaml content as Config attribute and allow patching it
without modifying the file (and reimport constants or config).

It also removes obsolete data in config_patch.yaml and moves several
functions in the right modules (Config)

JIRA: ARMBAND-334

Co-Authored-By: Cédric Ollivier <cedric.ollivier@orange.com>
Change-Id: I5c9a574d3283828063154c977cdfbc2abfdc6777
Signed-off-by: Linda Wang <wangwulin@huawei.com>
Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>