Senate tooltip add. Remove fish from granary store.
Gardens now may upgrade to square.
Senate infobox add.
Fix missing include

Fixes "invalid use of incomplete type 'class Tile'"
Fix ambiguous conversion

Related gcc error: conversion from 'const long int' to 'const value_type {aka const Variant}' is ambiguous
Needs check whether `int' is enough here.
Fix taking address of temporary
Fix reference assigning

Related gcc error: invalid initialization of non-const reference of type 'Picture&' from an rvalue of type 'Picture'
Fix calling template base class constructor
Remove byte order marks from sources
Merge pull request #160 from AMDmi3/gcc-fixes

Fix build errors
Fix CMake problem on windows

When building on Windows I got such message:

C:\Users\Roman\Documents\GitHub\opencaesar3\build>cmake ..
CMake Error at cmake/Modules/FindPackageHandleStandardArgs.cmake:97
(message):
Could NOT find PNG (missing: PNG_PNG_INCLUDE_DIR)
Call Stack (most recent call first):
cmake/Modules/FindPackageHandleStandardArgs.cmake:291
(_FPHSA_FAILURE_MESSAGE)

cmake/Modules/FindPNG.cmake:90 (find_package_handle_standard_args)
CMakeLists.txt:17 (find_package)

-- Configuring incomplete, errors occurred!

This commit fixes it
Prepare for boost dependent remove.
FileSystem improved. getting items list from directory improved.
Fix spelling
Merge pull request #162 from AMDmi3/spelling

Spelling fix
FindSDL.cmake improved. oc3_filesystem improved for work with linux. Lot of warnings fixed.
Merge branch 'master' of https://github.com/gecube/opencaesar3.

Conflicts:
	oc3_groupbox.cpp
	oc3_gui_info_box.cpp
	oc3_label.cpp
	oc3_pushbutton.cpp
Linux install way improved.
Forum move to oc3_forum.*. class TaxCollector add.
Finance adviser window add.