cshear: concurrent shearsort with pthreads

Build
-----
To build the program:

  $ make

To clear the directory of generated files:

  $ make clean

Run
---
There should be a file called input.txt in the root directory that contains
the matrix to be sorted.

  $ ./cshear.out

Bugs
----
- Output may not be formatted well for integers longer than 3 digits.

License
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The Unlicense