Added type of frequency clarification

[KronosTheLate]

In reading the documentation for fftfreqs, I did not find what I came there for - a clarification about if the frequencies were measured in oscillations/second, or radians/second. From my background (engineering student), I am used to talking about angular frequencies in most cases, and so the fact that normal frequency is returned was not obvious to me, an indication that it might not be to everyone. I have therefore appended the following line in the docs for fftfreq and rfftfreq:
The return values are not to be confused with angular frequency.

I considered specifying the unit of oscillation/second, but I felt like specifying this without adding "as opposed to..." was weird, and when adding it, it is longer and more trailing than this solution. Other suggestions are very welcome

[codecov]

Codecov Report

Merging #53 (a6c1437) into master (193d035) will decrease coverage by 4.75%.
The diff coverage is n/a.

❗ Current head a6c1437 differs from pull request most recent head ac9264e. Consider uploading reports for the commit ac9264e to get more accurate results

@@            Coverage Diff             @@
##           master      #53      +/-   ##
==========================================
- Coverage   52.63%   47.87%   -4.76%     
==========================================
  Files           2        2              
  Lines          95       94       -1     
==========================================
- Hits           50       45       -5     
- Misses         45       49       +4     

Impacted Files	Coverage Δ
src/definitions.jl	47.31% <ø> (-4.82%)	⬇️

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[KronosTheLate]

friendly bump

[jishnub]

Perhaps you may also add that the angular frequencies may be obtained by multiplying the output by 2pi

[KronosTheLate]

Perhaps you may also add that the angular frequencies may be obtained by multiplying the output by 2pi

Check. I am on my phone, so I could not find the UTF8 symbol for pi, but feel free to insert it id you can. Otherwise I think that 'pi' ia more reliable to display properly on e.g. phones.

[jishnub]

Yeah pi is better, and in any case is a valid identifier in Julia. Could you add back ticks to 2pi so that it displays as 2pi? This makes it clear that this is inline code.