parse out current version number in sphinx conf.py
add proper title to main page
[embind] Minimum RESERVED_FUNCITON_POINTERS not needed.

embind no longer calls Runtime.addFunction(), so a minimum
number of RESERVED_FUNCTION_POINTERS are no longer needed.
[docs] Sanitize whitespace.

(No whitespace at end of line, no tabs.)
[docs] Line wrap to be sanely readable / editable.
[docs] Document RESERVED_FUNCTION_POINTERS with addFunction.
[docs] Clean up whitespace.
[docs] Fix broken section marker.
avoid configure step in sdl2 port
clear sdl2-image when building sdl2, and improve logging
if port version file does not exist, retrieve the latest
handle length 0 in Pointer_stringify; fixes #2912
Merge pull request #2914 from waywardmonkeys/minor-doc-fix

Minor doc fix
Merge pull request #2915 from waywardmonkeys/add-function-docs

Add function docs
Merge pull request #2913 from waywardmonkeys/embind-and-reserved-function-pointers

[embind] Minimum RESERVED_FUNCITON_POINTERS not needed.
EMULATE_FUNCTION_POINTER_CASTS option
disable clang warnings when building sdl2 and sdl2-image
check for a missing directory in check_version in ports support code
Fix missing __lock / __unlock.

This was noticed as srandom / random use those.

Fixes issue #2916.
fix ports upgrades due to version changes