Schema configuration public API

Let's implement a public API classes for initial schema declaration. Considering next:

• It should be possible to create schema without having any Class instance, like we do now with QueryEntity. 
• Automatic schema creation based on annotated classes, like we have in ccfg.setIndexedTypes() IGNITE-13749
• Transient fields semantic. IGNITE-13749
• Using builder pattern for schema configuration.
• Split type-system into internal native-types (introduced IGNITE-13617) and public API types. The latest ones should be portable (e.g. could be used in .Net)
• API can be extracted to separate module that will not have any dependency on other Ignite modules.