Style fixes on paramater_io.cpp
Finish encoding_packet class.

- Make all member functions const.
- Move destructor to cpp file.
- Implemented payload(void) method
    - as_array(void) and as_buffer(void) call this as well
    - returns the payload_id, num_symbols, and symbols as a byte vector
- Implement write_to(vector<uint8_t>*) method
    - appends the output of payload to the given vector
    - add tests to test basic behaviour.
Add destructor
Revert "Add destructor".

This reverts commit c04964cec11848a2afc4aa88f4ca6e556b82e78e.
Remove destructor for encoding packet for now
Use unsigned return types for encoding_packet
encoding_symbol is partially done.
Padded byte array compiles, awaiting error handling
Fix for previous commit, forgot file.
Completed padded byte array error checks
Restyled new files
Added index to padded byte array
Added OSX as test target
Const the fec_parameters functios.
array_data_encoder almost done. Core functionality missing.

- get_source_block_encoders is not done.
Fixed license header in rand
Fix wrong Kt_max value.
Changed Z to uint16_t outside of OTI, fixes #7
Merge branch 'develop' into feature/encoder

* develop:
  Changed Z to uint16_t outside of OTI, fixes #7

Conflicts:
	include/parameters/fec_parameters.h
	src/parameters/fec_parameters.cpp
	src/parameters/parameter_io.cpp
Add header file for linear_system