Added make_decimal()
exclude sqlite3 component from default build
Fixed the generated include statement for dependent module

Using the quoted include statement instead of the angled include statement.
Added support for MPC build system
Added value holder types for vector based types.

The value holder types include ascii_string_type, unicode_string_type, byte_vector_type, int_vector_type. Those types may be useful when temporary swapping the content of a mutable reference without copying.