dev-python/tablib: fix broken package

* Dependencies were both incomplete and spurious
* Fix tests which were failing for many different reasons

Bug: https://bugs.gentoo.org/659790
Bug: https://bugs.gentoo.org/621884
Package-Manager: Portage-2.3.44, Repoman-2.3.10

dev-python/tablib/files/tablib-0.12.1-no-ujson.patch

@@ -0,0 +1,16 @@
+diff --git a/tablib/formats/_json.py b/tablib/formats/_json.py
+index a3d6cc3..4c2777a 100644
+--- a/tablib/formats/_json.py
++++ b/tablib/formats/_json.py
+@@ -6,10 +6,7 @@ import decimal
+ 
+ import tablib
+ 
+-try:
+-    import ujson as json
+-except ImportError:
+-    import json
++import json
+ 
+ title = 'json'
+ extensions = ('json', 'jsn')

dev-python/tablib/tablib-0.12.1-r1.ebuild

@@ -0,0 +1,45 @@
+# Copyright 1999-2018 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=7
+PYTHON_COMPAT=( python{2_7,3_{5,6}} )
+
+inherit distutils-r1
+
+DESCRIPTION="A format-agnostic tabular dataset library written in Python"
+HOMEPAGE="http://python-tablib.org/"
+SRC_URI="mirror://pypi/${PN:0:1}/${PN}/${P}.tar.gz"
+
+SLOT="0"
+LICENSE="MIT"
+KEYWORDS="~amd64 ~x86"
+IUSE="test"
+
+RDEPEND="
+	dev-python/odfpy[${PYTHON_USEDEP}]
+	dev-python/openpyxl[${PYTHON_USEDEP}]
+	dev-python/pyyaml[${PYTHON_USEDEP}]
+	dev-python/unicodecsv[${PYTHON_USEDEP}]
+	dev-python/xlrd[${PYTHON_USEDEP}]
+	dev-python/xlwt[${PYTHON_USEDEP}]
+"
+
+# Presence of pandas older than v0.23 makes tablib tests (which sometimes tries
+# to load pandas dataframes) fail.
+DEPEND="
+	dev-python/setuptools[${PYTHON_USEDEP}]
+	test? (
+		${RDEPEND}
+		dev-python/pytest[${PYTHON_USEDEP}]
+		!<dev-python/pandas-0.23
+	)
+"
+
+PATCHES=(
+	# https://github.com/kennethreitz/tablib/issues/297
+	"${FILESDIR}/${PN}-0.12.1-no-ujson.patch"
+)
+
+python_test() {
+	pytest -v -v  || die
+}