Refactor

refactor counters
add raw flow decoding
add flow files
add GetRecords() to samples
Update docs, remove unreachable code
Add raw packet flow encoding
Add an encoder
update README badges
Make numRecords private

Otherwise there might be inconsistencies between
len(s.Records) and that field.
Increment sequence number after encoding
Use pointer to Encoder, fix encoding
Merge pull request #20 from PreetamJinka/19-refactor

Refactor package