Added tests for atomic.py

[vidit23]

I had to update my forked repository so, I combined all the seperate PR into one.
There are tests forthe following functions in atomic.py
read_lines_data
read_zeta_data
read_collision_data

[landscape-bot]

Code quality remained the same when pulling e0fc59e on vidit23:master into dca3806 on tardis-sn:master.

[landscape-bot]

Code quality remained the same when pulling 948dbbf on vidit23:master into 4cdaaf0 on tardis-sn:master.

[coveralls]

Coverage increased (+0.64%) to 55.74% when pulling 948dbbf on vidit23:master into 4cdaaf0 on tardis-sn:master.

[landscape-bot]

Code quality remained the same when pulling 82a1676 on vidit23:master into 4cdaaf0 on tardis-sn:master.

[landscape-bot]

Code quality remained the same when pulling c1f3cf5 on vidit23:master into 4cdaaf0 on tardis-sn:master.

[landscape-bot]

Code quality remained the same when pulling 8cbf94b on vidit23:master into 4cdaaf0 on tardis-sn:master.

[vidit23]

I tried using Cython wrappers to make some tests for cmontecarlo.c but it didnt work out. I'll keep working on it. I am also looking into using SWIG or manual wrapping of C function.

[coveralls]

Coverage increased (+0.64%) to 55.74% when pulling 8cbf94b on vidit23:master into 4cdaaf0 on tardis-sn:master.

[coveralls]

Coverage increased (+0.64%) to 55.74% when pulling 8cbf94b on vidit23:master into 4cdaaf0 on tardis-sn:master.

[coveralls]

Coverage increased (+0.64%) to 55.74% when pulling 8cbf94b on vidit23:master into 4cdaaf0 on tardis-sn:master.

[coveralls]

Coverage increased (+0.64%) to 55.74% when pulling 8cbf94b on vidit23:master into 4cdaaf0 on tardis-sn:master.

[landscape-bot]

Code quality remained the same when pulling cf8bb16 on vidit23:master into 4cdaaf0 on tardis-sn:master.

[coveralls]

Coverage increased (+0.64%) to 55.74% when pulling cf8bb16 on vidit23:master into 4cdaaf0 on tardis-sn:master.