Qiime2 metadata table maker

Qiime2MetadataTableMaker class.

[Mandatory]: - fastq_folder must contains all fastq files (paired or not).

- Create metadata table from a fastq folder. User can add metadata information in a tab formated table after the first three columns:

    For paired-end files :
        #author:
        #data:
        #project:
        #types_allowed:categorical or numeric
        #metadata-type  categorical categorical
        sample-id   forward-absolute-filepath   reverse-absolute-filepath
        sample-1    sample0_R1.fastq.gz  sample1_R2.fastq.gz
        sample-2    sample2_R1.fastq.gz  sample2_R2.fastq.gz
        sample-3    sample3_R1.fastq.gz  sample3_R2.fastq.gz

    For single-end files :
        #author:
        #data:
        #project:
        #types_allowed:categorical or numeric
        #metadata-type  categorical
        sample-id   absolute-filepath
        sample-1    sample0.fastq.gz
        sample-2    sample2.fastq.gz
        sample-3    sample3.fastq.gz