Link msgpuck statically when use the submodule

[Totktonada]

Because trying to install libmsgpuck.so within a tarantool-c package can clash with system-wide msgpuck package.

[Totktonada]

Subtask: #96.

[Totktonada]

We should provide two options:

• Build with statically linked libmsgpuck.a from the submodule.
• Build with system-wide libmsgpuck.so.

The former should be default to easily build and test. The latter however is mandatory for packaging.