Updated README.md and updated required packages to include mio

[anuramubc]

• Added further instructions on installing dependencies and building trx-cpp.
• Added mio to required packages in tests/CMakeLists.txt

To do:

• As discussed we are going to stick with C++ 11 as our anciptaed user uses MRtrix3(https://www.mrtrix.org/) that uses C++ 11. So, we need to use the appropriate google test framework that supports C++ 11.
• Currently facing this error while building trx-cpp - "error: use of undeclared identifier 'canonicalize_file_name" orginating from src/trx.tpp line 1097. Tried including stdlib.h in header file but that did not resolve this error.

[arokem]

Looks like I will have to approve running actions here until we merge your first PR on the repo, unless I make you a contributor, which I will now do. Hopefully that will do the trick so that I don't have to approve it with each push you make.

[arokem]

looks like you have CI working to build this? Does this mean that the PR addresses all of the points in the original message above? Shall we review and merge this PR and then move on from there?

[anuramubc]

• The CI addresses most of the concerns. However, I still want to have a CI workflow to run unit tests, since the change I made is in the cmkae file in tests.

• I'm running into a peculiar problem if I try to build trx-cpp locally on my Mac with clang compiler it throws me an " error: use of undeclared identifier 'canonicalize_file_name" originating from src/trx.tpp line 1097". But this gets resolved if I use realpath(path, NULL) function - which does the same job as the canonicalize_file_name() function. I need to try to change my compiler to g++ and see if I can build it successfully without that error.