#2 Bug fixes from matplotlib's vendored copy of Agg

[Thomas A Caswell]

For several years now Matplotlib (https://github.com/matplotlib/matplotlib) has been maintaining a fork of the 2.4 version of Agg which has been accumulating bug fixes. Now that this looks active again, we would like to move as many of these as possible upstream!

I have attached diffs of:

• between our current master branch and the current svn (agg_patch.patch)
• a git diff of when we updated to 2.4 until the current master branch viagit diff -M1 121ee67b4d4d0e14dea4c52efd6d353811e2e386..master -- extern/agg24-svn/* extern/agg24/* agg24/* > /tmp/git_history.patch
• a git diff from when we updated to svn r103 to our current mastre branch via git diff -M1 2a178393c00d0d234c4b59c190cc26fb6eee5cd7..master -- extern/agg24-svn/* extern/agg24/* agg24/* > /tmp/from_103.patch

This is particuarly relavent because mapnik has also been maintaining a fork which now has conflicting symbol (see https://github.com/matplotlib/matplotlib/issues/7537 and https://github.com/mapnik/mapnik/issues/3565). The best solution is for both projects local changes to make it upstream and have a new 2.x Agg release.

Please let me know what we can do to make this go smoothly!

Commits that touch our vendored copy:

720731083868f4c914daf6810bedad34cd76bf4d
2e1f97dd8b7f5360f210a055f359d7544cedc589
963faed6fb19ce0034766c4e8dcac36f84900f53
46592b2214e36efc8e718edb70e23ae0e0c99030
bba056499457b04b190d4c063cf844745789b46e
99f63576e1ee0861537c5b42c7cc6c0a1809ddbc
659513951920d83fe6ef68ec40dd72f7bd6d6653
2c06419fd374ee410163c7c55763dbc9590a99b9
cf80280584757ca9569596dd2dc6dc5423c7f92f
86c4436617d11a5e842e3088c81d34b6ca0d4413
1b937a4fea5a65d0f3904da848d6aa4044fb2abf
2a178393c00d0d234c4b59c190cc26fb6eee5cd7
0d288b3bc623e0bb4354a779d12950405bf1a4ff
4301543c3df4990a9200d60ca94697f81205e863
7e6d55aa0148fa567656b80d0b463e2e8a84c702
d4ec93f6fa0015eadf333556c46b9c467ae2c202
55f052fd5fd1116e251ffbed2719be2d222e7af5
a0b0080b9b2ba4365c65587a09e9e82d7a32c65a
634b683baa6309cd989e28ab8cbd3d52f6811c8c
0473bb1ed5728ab665710911ca84c4cdedf4bc00
3760cf10546024adb36b111892c8db7d7fcf3f0d
6f18cf880659c6379d4468bd07a61efa035b1437
e9fcc085c340f60e869048b254f1142f63473544
8caeeaeb30206bf6e6d0c196b57214421ac278a3
1c454574ab6115634913c5ec8cf27310ecc14cf8
c499de9cfd308335b0ff8dbc39a27eac1d204bc0
121ee67b4d4d0e14dea4c52efd6d353811e2e386

via git log --format=%H -- extern/agg24-svn/* extern/agg24/* agg24/*