[1.5.x] Minor edits to latest release notes.

Backport of 860d31ac7a3bdd4b27db8b34b110b3d801ddaf8a from master
[1.5.x] Fixed #22167 -- Improved documentation on context processors

Backport of e7ffba8f78849fbf60b98fb8d67ef4577b585e3b from master.
[1.5.x] Fixed case in form widgets docs

Backport of 9494f29d from master
[1.5.x] Fixed #22644 -- Clarified documentation for NamedUrlWizardView

Backport of 727d048f0991ccbd1564c6fb225ffbfd2f1a2102 from master.
[1.5.x] Improved deprecation plan links in release notes.

Backport of 7ff326928a08d4c51141768bd305a44ca5ecb2e7 from master
[1.5.x] Fixed #22842

Backport of 7a1f8414c3b71b6af03e5be9f5f8db115551c410 from master.
[1.5.x] Fixed #22859 -- Improved crossDomain technique in CSRF example.

Thanks flisky for the report.

Backport of 0be4d64487 from master
[1.5.x] Fixed #22966 -- Clarified which release notes appear for each doc version.

Thanks haimunt at yahoo.com for the suggestion.

Backport of e6b3d6c22f from master
[1.5.x] Fixed #13794 -- Fixed to_field usage in BaseInlineFormSet.

Thanks sebastien at clarisys.fr for the report and gautier
for the patch.

Backport of 5e2c4a4bd1 from master
[1.5.x] Revert "Fixed #13794 -- Fixed to_field usage in BaseInlineFormSet."

This reverts commit 4ae68f677b3348765d8649d8b57beffa18fe8d3d.

stable/1.5.x branch is in security-fixes-only mode.
[1.5.x] Fixed #23149 -- Clarified note on HTTPOnly in cookie-based session docs

Backport of e26366da44bb343e7a95d01ff0dd18b8026c2802 from master.
[1.5.x] Fixed #23239 -- Clarified a phrase in the contrib.markup docs.
[1.5.x] Removed a doc reference to the deprecated `mimetype` kwarg.

Backport of 61ed959235 from master
[1.5.x] Noted that django-jython requires Django 1.7.

Backport of 72e98d5c16 from stable/1.6.x
[1.5.x] Fixed #23267 -- Fixed typo in Translation documentation

Thanks to Tomin1 for the report.

Backport of 2e7be92b4df29ac851d570e57da5dcf756c5ac52 from master.
[1.5.x] Added a warning that remove_tags() output shouldn't be considered safe.

Backport of 7efce77de2 from master
[1.5.x] Corrected content_type parameter name in sitemap docs.

mimetype was deprecated in 1.5 per 11ec0253ab4cc926ab9e77619132cb398231ac33.

Backport of a7443c24a3 from master
[1.5.x] Added release note stubs for 1.5.9 and 1.4.14.
[1.5.x] Prevented reverse() from generating URLs pointing to other hosts.

This is a security fix. Disclosure following shortly.
[1.5.x] Fixed #23157 -- Removed O(n) algorithm when uploading duplicate file names.

This is a security fix. Disclosure following shortly.