Add Reverse Search in bash

### Bash

* [`grep`ping text](bash/grepping-text.md)

* [Listing files](bash/listing-files.md)

* [Reverse Search](bash/reverse-search.md)

### C++

* [`const` unless it can't be](cpp/const-unless-it-cant-be.md)

Reverse Search

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When we want to use a command that we have used before, we can search for it in the bash history by pressing `Ctrl-R` and then start typing the command we want to search. The current match wil be displayed and when we land on the right match, pressing `Enter` runs the command.