Renames the keyword table_area to table_areas (#171)

`table_areas` sounds more apt since it is a list and there can be
multiple table areas on a page.

Closes #165

tests/data.py

@@ -81,7 +81,7 @@ data_stream_table_rotated = [
     ["", "", "", "", "", "", "", "", "54", "", "", "", "", "", "", "", "", ""]
 ]
 
-data_stream_table_area = [
+data_stream_table_areas = [
     ["", "One Withholding"],
     ["Payroll Period", "Allowance"],
     ["Weekly", "$71.15"],
@@ -261,7 +261,7 @@ data_lattice_table_rotated = [
     ["Pooled", "38742", "53618", "60601", "86898", "4459", "21918", "27041", "14312", "18519"]
 ]
 
-data_lattice_table_area = [
+data_lattice_table_areas = [
     ["", "", "", "", "", "", "", "", ""],
     ["State", "n", "Literacy Status", "", "", "", "", "", ""],
     ["", "", "Illiterate", "Read & Write", "1-4 std.", "5-8 std.", "9-12 std.", "College", ""],

tests/test_common.py

@@ -45,11 +45,11 @@ def test_stream_table_rotated():
     assert df.equals(tables[0].df)
 
 
-def test_stream_table_area():
-    df = pd.DataFrame(data_stream_table_area)
+def test_stream_table_areas():
+    df = pd.DataFrame(data_stream_table_areas)
 
     filename = os.path.join(testdir, "tabula/us-007.pdf")
-    tables = camelot.read_pdf(filename, flavor="stream", table_area=["320,500,573,335"])
+    tables = camelot.read_pdf(filename, flavor="stream", table_areas=["320,500,573,335"])
     assert df.equals(tables[0].df)
 
 
@@ -100,11 +100,11 @@ def test_lattice_table_rotated():
     assert df.equals(tables[0].df)
 
 
-def test_lattice_table_area():
-    df = pd.DataFrame(data_lattice_table_area)
+def test_lattice_table_areas():
+    df = pd.DataFrame(data_lattice_table_areas)
 
     filename = os.path.join(testdir, "twotables_2.pdf")
-    tables = camelot.read_pdf(filename, table_area=["80,693,535,448"])
+    tables = camelot.read_pdf(filename, table_areas=["80,693,535,448"])
     assert df.equals(tables[0].df)
 
 

tests/test_errors.py

@@ -34,11 +34,11 @@ def test_unsupported_format():
 
 
 def test_stream_equal_length():
-    message = ("Length of table_area and columns"
+    message = ("Length of table_areas and columns"
                " should be equal")
     with pytest.raises(ValueError, message=message):
         tables = camelot.read_pdf(filename, flavor='stream',
-            table_area=['10,20,30,40'], columns=['10,20,30,40', '10,20,30,40'])
+            table_areas=['10,20,30,40'], columns=['10,20,30,40', '10,20,30,40'])
 
 
 def test_no_tables_found():