update playturn.cpp
fixup build after 'remove unused functions + fix comments'
fix quit game durign linger mode

this prevents an assertion error.
move impl of tstring database to tstring.cpp
move headers one file forwards
advance boost headers one step forwards
remove some unnecessary includes
move include from a header to its compilation unit

This include is apparently unnecessary but we don't compile without
it... it seems to only affect this compilation unit though.
fixup includes in headers, started as just config, but led to more

The changes in config required changes in ai/contexts which
cascaded, also many places were throwing game::game_error without
including its definition except from config.
attempt to fix travis compilation
attempt to fix travis compilation
Revert "attempt to fix travis compilation"

This reverts commit 6e3e8990e8a1b2cbcddf6738c7b63a5cfd0fc4a5.
remove unnecessary include from header, despite what iwyu tool says
move village_owner function to display_context

I would have liked to put it in game_board, but it is needed for
reports so it can't go there
move is_observer to gameboard, with accessor in playcontroller
LoW S7: Dialogue change/Message Fix

Dialogue changed to have proper English formatting.  Eradion death
message fixed to remove potential of an enemy side expressing concern
over his death.
LoW S9: Message on Dwarf Recruitment

Current message read as if Kalenz could recruit dwarves.  It has been
changed to make it clear that only Olurf can recruit dwarves for Kalenz.
Fix a memory leak in forum_user_handler
Fix memory leak in wesnothd
LoW S10: Added "or" to objectives

Previously the objectives were written in a way that indicated the
player would need to complete both.