Readme examples

[lrq3000]

Update the Readme with a Usage chapter and a detailed example on how to make a good progress bar.

[codecov-io]

Current coverage is 100.00%

Merging #66 into master will not affect coverage as of 8a2562b

@@            master     #66   diff @@
======================================
  Files            5       5       
  Stmts          221     221       
  Branches        46      46       
  Methods          0       0       
======================================
  Hit            221     221       
  Partial          0       0       
  Missed           0       0       

Review entire Coverage Diff as of 8a2562b

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[lrq3000]

Thank's for the fix @casperdcl 👍