Review, add and improve unit tests

[GegznaV]

Review, fix, add and improve unit tests for these functions and their helpers:

• count_lines

• read_asc_Andor
• read_asc_PerkinElmer

• read_txt_Shimadzu

• Features/42 read txt horiba t #48
• Features/42-read-txt-horiba-xy #49
• Improve unit tests for read_txt_Horiba_*() #72
  • read_txt_Horiba
  • read_txt_Horiba_t
  • read_txt_Horiba_xy

• [LOW PRIORITY, may skip for now] Add unit tests to read_ini() #74
  • read_ini

• Improve unit test for read_txt_Renishaw() #70
  • read_zip_Renishaw
  • read_txt_Renishaw

• Improve WITec unit tests #75
  • read_dat_Witec
  • read_txt_Witec
  • read_txt_Witec_Graph
  • read_txt_Witec_TrueMatch

• Add unit tests to read_txt_PerkinElmer() #73

[GegznaV]

In unit tests, make sure to check that the values in each hyperSpec slot (@data (non-spectra), @data$spc (spectra), @wavelength, and @label) are checked and that column names of @data and @data$spc are correct. This will let us detect discrepancies easier than just by using hash code.

[GegznaV]

@sangttruong, I assign this to you, as hySpc.read.txt is mentioned in your GSoC proposal. OK?

Create a separate branch for each file so that it was easier to review.

[GegznaV]

This is not closed yet!