Added remap.py unit test

[bombaci-vsc]

This is a step towards improving the test coverage, espically when vendor data isn't available to run the converters.

In master

$ pytest --cov=sarpy.visualization.remap --cov-report term-missing

Name                                                                                                                   Stmts   Miss  Cover   Missing
----------------------------------------------------------------------------------------------------------------------------------------------------
sarpy/visualization/remap.py     574    400    30%   28-29, 61-64, 100-126, 149, 175-179, 213-218, 228, 231-234, 243, 254-259, 269, 280-284, 292-299, 308, 331, 358, 364, 371-381, 406, 435-437, 445, 448-457, 462, 465, 517-525, 533, 536-539, 546, 549-552, 559, 563-567, 576, 600-604, 633, 642-643, 660, 685, 710, 747-758, 765, 769-775, 783, 787-793, 802, 809-828, 859-879, 915, 924-925, 955-962, 969, 973-979, 987, 991-997, 1006, 1013-1032, 1063-1084, 1120, 1129-1130, 1173-1175, 1186, 1210-1214, 1243, 1252, 1289-1295, 1303, 1306-1314, 1323, 1326-1333, 1341, 1344-1347, 1353-1364, 1373, 1398-1428, 1458, 1467-1468, 1508-1519, 1530, 1537, 1540-1542, 1550, 1556-1575, 1583, 1603, 1609, 1616, 1640-1653, 1658-1686, 1698-1700, 1713-1719, 1742-1749, 1775-1779, 1796-1800, 1817-1821, 1838-1842, 1862-1866, 1886-1890, 1908-1912, 1932-1936
----------------------------------------------------------------------------------------------------------------------------------------------------
TOTAL                                                                                                                    574    400    30%

The added unit test

$ pytest --cov=sarpy.visualization.remap --cov-report term-missing tests/visualization/test_remap.py 

Name                           Stmts   Miss  Cover   Missing
------------------------------------------------------------
sarpy/visualization/remap.py     574     49    91%   28-29, 299, 371-381, 559, 642-643, 810, 812, 826, 876, 924-925, 974, 978, 996, 1014, 1016, 1030, 1129-1130, 1252, 1327, 1362, 1421, 1467-1468, 1550, 1559, 1568, 1571, 1583, 1616, 1641, 1659, 1671-1672, 1675-1676, 1679-1680, 1683-1684, 1714
------------------------------------------------------------
TOTAL                            574     49    91%

There are some parts of remap.py which rely on SICD reader objects, so those code paths aren't yet tested.

[Darder]

included in new update version 1.3.10