fixup a null ptr deref in help.cpp when viewing from editor

I think this was introduced when I eliminated resources::gamemap,
I didn't realize this needed to get that from display rather than
the gameboard.
fixup src/cmakelists.txt

Ivanovic pointed out problems:
http://www.wesnoth.org/irclogs/2014/07/%23wesnoth-dev.2014-07-20.log
revert movement of unit alignment init to initializer list 

This fixes a bug unit aligment beeing ignored when creating a unit.

Setting this value in the initializer list has no effect becaue it is overwritten by advance_to().

this was changed in https://github.com/wesnoth/wesnoth/commit/30c179b92da29bb03541e8e0c7dfaf1c3c401b35#diff-af3fd7e884f8ab9f39f9088ca4010d0dR1738.
Auto generate sections for all eras and their factions

This fills Feature Request #22107.
port faction description text from the wiki to the in-game help

This commit ports the text I found as the introductions to wiki
pages like this http://wiki.wesnoth.org/Drakes into the in-game
help, preserving the links to race descriptions and eras.
add portraits to decorate mainline faction descriptions
silence a warning coming from the help log channel
add race and alignment listings to the help topics for factions
Merge branch 'eras_sections'
update changelogs
Fix base_width and base_height.

No comment.
Use base_width and base_height where appropriate.
Use base_width and base_height where appropriate.
timage::width/height returns scaled and clipped dimensions.

Instead of just scaled.
Fix report images.
Use base_height where appropriate.
Enable local ToD in SDL_gpu builds.
Draw minimap units in SDL_gpu builds.
SDL_gpu support for GUI1 buttons.
Don't recreate buttons for every draw.