User manual: online execution of checksum sample app

[deining]

See discussion here.

[codecov-commenter]

Codecov Report

Merging #1200 into master will increase coverage by 0.00%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master    #1200   +/-   ##
=========================================
  Coverage     94.30%   94.30%           
  Complexity      455      455           
=========================================
  Files             2        2           
  Lines          6674     6676    +2     
  Branches       1794     1795    +1     
=========================================
+ Hits           6294     6296    +2     
  Misses          102      102           
  Partials        278      278           

Impacted Files	Coverage Δ	Complexity Δ
src/main/java/picocli/CommandLine.java	94.14% <0.00%> (+<0.01%)	314.00% <0.00%> (ø%)

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[remkop]

Sorry, I am very picky about especially the beginning of the user manual.
Please don't take this as criticism, but as positive feedback!

[deining]

Sorry, I am very picky about especially the beginning of the user manual.
Please don't take this as criticism, but as positive feedback!

I like the way we interact and cooperate on this project.
Don't merge anything that you are not convinced of.
In the past, your comments always lead to an inprovement in some or the other way, let's go ahead with this!

[remkop]

Merged. Thanks a lot, this is pretty cool!
I made the text as terse as possible, I hope you like it.