labcomm_encode_type_index, labcomm_encoder_end

Added test of generated C encoders.

encoder indices (linker magic provided). 

Testcase for some of the encoding/decoding functions.

split parser stack into val_ and ptr_ + added signature_name_length to work around handling varint lengths

changed generated length to be without user_id field + started changing the sig_parser to build signature_t objects

added a small comment on the packing + added untested code to the csharp lib + changed BASE_UID to 0x60