Add input validation in substitution_mapping class

Add input validation in substitution_mapping class

Add input validation in class of substitution_mapping according to
specification of
http://docs.oasis-open.org/tosca/TOSCA-Simple-Profile-YAML/v1.0/
TOSCA-Simple-Profile-YAML-v1.0.html:
1) The properties of substituted node template which be mapped must be
in the inputs of nested service template which defines substutition
mappings;
2) The inputs of nested service template which are not in properties of
the substituted node template must have default values.
3) If the properties of node_type is required and no default value,
 must provide inputs for them;
4) Property names and the input names must be the same.

JIRA:PARSER-79

Change-Id: Ie4664fe17c8279ad531ac9acec057f98d4e9281a
Signed-off-by: shangxdy <shang.xiaodong@zte.com.cn>