Function to parse queries and apply to the GFF file

[lpantano]

The idea is to have an option shared by many functions called --query, that allows filtering of the GFF format for:

• Name, Variant, Filter, type values of the GFF format. To learn about where they are in the line of the GFF file go to: https://github.com/miRTop/incubator/blob/master/format/definition.md
• It should allow: ==, !=, ~// (regular expression)
• Allows and , or operations
  The option should be added here: https://github.com/miRTop/mirtop/blob/dev/mirtop/libs/parse.py. Probably under the function counts (it would be there soon)

And the function that parse the query value should be here: https://github.com/miRTop/mirtop/blob/dev/mirtop/gff/query.py

The idea should be something like this:

mirtop counts -i GFF -o OUTFOLDER --query "Filter == PASS and Name~/let-7/"

That should get the GFF file, apply the query filters, and then do whatever counts function makes.

This issue can be resolved with a single function that work with the --query value and a line of the GFF file, given TRUE or FALSE, depending on the query.

Test unit should be implemented at https://github.com/miRTop/mirtop/blob/dev/test/test_functions.py