Add basic usage information on README [skip ci] #673

1. 
   kroggen commented at 4:40 am on October 11, 2019: none

   This may not be so good documentation, but at least it is a start. Feel comfortable to fix it.

   #672

2. Add basic usage information on README [skip ci] dc002e08de
3. 
   kroggen commented at 4:52 am on October 11, 2019: none

   What about changing “key generation” on README to “public key generation”?
4. 
   jonasnick commented at 11:58 am on October 11, 2019: contributor

   I’m in favor of adding a Usage section, but the bullet points in this PR seem a bit out of place. Much more helpful would be to provide examples for pubkey generation, signing and verification and add a link to the include files for the documentation.
5. 
   real-or-random commented at 5:01 pm on May 8, 2020: contributor

   Closing in favor of #748.
6. real-or-random closed this on May 8, 2020

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kroggen jonasnick real-or-random