[docs] EOSIO Implementation, see below

[sunshineveg]

File: [docs/20_eosio-terminology/index.md](https://github.com/EOSIO/welcome/blob/develop/docs/20_eosio-terminology/index.md)

We are comparing block chain terminology to the EOSIO implementation. Change the phrase "EOSIO Term/Terminology" to "EOSIO implementation". Also check the usage in the introductory paragraph.

Also, do not use the word "term", spell it out - Terminology.