Add linter

[alvarofpp]

No description provided.

[alvarofpp]

I changed Makefile lint command to:

.PHONY: lint
lint:
	@docker pull ${DOCKER_LINTER_IMAGE}
	@docker run --rm -v ${ROOT}:/app ${DOCKER_LINTER_IMAGE} " \
		lint-commit ${LINT_COMMIT_TARGET_BRANCH} \
		&& lint-markdown \
		&& lint-python urnai"

I used make lint > errors.txt to get all occurrences of errors.

The code to count the number of occurrences of each error:

import re
from collections import Counter

# Counts the number of occurrences of each error
with open('errors.txt', 'r') as file_errors:
  errors = [re.search('[A-Z]{1}[0-9]{3}', row).group(0) for row in file_errors.readlines()]
  counter = Counter(errors)

We have a total of 5954 errors.

---

Error groups

Error group	Occurrences	Description
C8	40	Missing trailing comma
D2	134	Whitespace issues
D3	73	Quotes issues
D4	116	Docstring content issues
E1	190	Indentation
E2	1145	Whitespace
E3	283	Blank line
E4	62	Import
E5	782	Line length
E7	72	Statement
F4	766	Module
F5	1	%
F8	54	Variable (underfined name)
I1	249	Import statements
I2	162	Import groups
Q0	964	Quotes
W1	1	Indentation warning
W2	842	Whitespace warning
W3	16	Blank line warning
W6	2	Deprecation warning

Top 10 errors

Code	Occurrences	Description or example message
Q000	849	remove bad quotes
E501	782	line too long (82 > 79 characters)
W291	600	trailing whitespace
F405	566	name may be undefined, or defined from star imports: module
E203	353	whitespace before ,, ; or :
E265	273	block comment should start with #
W293	231	blank line contains whitespace
I100	225	your import statements are in the wrong order
E231	195	missing whitespace after ,, ; or :
F401	191	module imported but unused

All errors

Code	Occurrences
C812	37
C815	2
C819	1
D200	30
D202	7
D204	13
D205	59
D208	21
D210	1
D211	3
D300	73
D400	64
D401	51
D403	1
E101	1
E111	2
E114	11
E116	4
E117	11
E122	34
E124	3
E127	35
E128	86
E129	1
E131	2
E201	15
E202	35
E203	353
E211	10
E221	4
E225	55
E231	195
E251	176
E252	2
E261	13
E262	7
E265	273
E266	7
E301	6
E302	166
E303	108
E305	3
E401	16
E402	46
E501	782
E701	19
E703	1
E711	40
E713	4
E722	6
E741	2
F401	191
F403	9
F405	566
F523	1
F811	19
F821	12
F841	23
I100	225
I101	24
I201	153
I202	9
Q000	849
Q001	41
Q002	73
Q003	1
W191	1
W291	600
W292	11
W293	231
W391	16
W605	2