[1.4.x] Fixed geos test to prevent random failure

Points in the test fixtures have 20 as max coordinate.

Backport of 87854b0bdf354059f949350a4d63a0ed071d564c from master.
[1.4.x] Bump version post-release.
[1.4.x] Cleaned up 1.4.8 release notes

Backport of 8d29005524 from master
Revert "[1.4.x] Ensure that passwords are never long enough for a DoS."

This reverts commit 3f3d887a6844ec2db743fee64c9e53e04d39a368.

This fix is no longer necessary, our pbkdf2 (see next commit) implementation
no longer rehashes the password every iteration.
[1.4.x] Fixed #21138 -- Increased the performance of our PBKDF2 implementation.

Thanks go to Michael Gebetsroither for pointing out this issue and help on
the patch.

Backport of 68540fe4df44492571bc610a0a043d3d02b3d320 from master.
[1.4.x] Fixed #21248 -- Skipped test_bcrypt if no py-bcrypt found

Pre 1.6 Django worked only with py-bcrypt, not with bcrypt. Skipped
test_bcrypt when using bcrypt to avoid false positives.

Backpatch of 9f8a36eb20895d9e542820d5190bfa77ad1b85d9 from stable/1.5.x.
[1.4.x] Fixed #21256 -- Error in datetime_safe.datetime.combine.

Backport of d9b6fb8 from master
[1.4.x] Fixed #21253 -- PBKDF2 with cached HMAC key

This gives a 2x speed increase compared to the existing implementation.

Thanks to Steve Thomas for the initial patch and Tim Graham for finishing it.

Backport of 1e4f53a6eb8d1816e51eb8bd8f95e704f6b89ead from master.
[1.4.x] Added 1.4.9 release notes

Backport of 2eb8f15516 from master
Fixed #13245: Explained Oracle's behavior w.r.t db_table
and how to prevent table-name truncation

Thanks russellm & timo for discussion, and timo for review.

Backported from master 317040a73b77be8f8210801793b2ce6d1a69301e
[1.4.x] Bumped release date for 1.5.5 & 1.4.9.

Backport of 4ce5c119b5 from master
[1.4.x] Bump everything for 1.4.9 bugfix release.
Merge tag '1.4.9' into nonrel-1.4

Tag '1.4.9'