Improve input logic

[ajandria]

Description of feature

Currently pipeline requires a sample sheet containing path where IDATs are located and also a path to a sample sheet with metadata. This can surely be changed so that the pipeline requires a sample sheet with all of the information rather than a sample sheet which contains path to two independent files.

When that is done we can then also just add phenotypes directly in a single file, rather than using another file like it is being done currently (--sample_metadata).

New sample sheet used for the --input should look something like this:

sample,idat_red,idat_green,group,pheno_age,pheno_bmi,pheno_sex
GSM1075838,	https://ftp.ncbi.nlm.nih.gov/geo/samples/GSM1075nnn/GSM1075838/suppl//GSM1075838_6929689021_R01C01_Red.idat.gz,https://ftp.ncbi.nlm.nih.gov/geo/samples/GSM1075nnn/GSM1075838/suppl//GSM1075838_6929689021_R01C01_Grn.idat.gz,control,34,25,male

This would be then more aligned with a standard nf-core sample sheet idea that can also be used for populating meta map

[ajandria]

Samplesheet for test-full: https://github.com/ajandria/test-datasets/blob/methylarray/testdata/test_full/input_test_phenos.csv