Made clearifications and referenced INSTALL_LINUX and INSTALL_WINDOWS for install instructions.
Formatting.
Merge pull request #98 from Rovanion/install-instructions

Install instructions
Additional instruction fixes
Tested and woring openSUSE instructions.
All information from BuildingOpenCaesar3.md has been duplicated or moved into README or the INSTALL files.
Additional instructions if the user compiled boost.
Added more examples of resolutions
Fixed 7za instruction
Rebase to master/0.2
Test commit
First attempt at implementing a timer for benchmarking
Merge pull request #99 from Rovanion/install-instructions

Streamlining of install instructions
Put overlay menu text in localisation lookups
Added new English language localisation (locales/en.po)
Included missed header file oc3_gettext.hpp in oc3_overlays_menu.cpp
Put overlay button text into localisation lookup (##ovrm_text##, oc3_menu.cpp)
Put main menu button text into localisation lookups (oc3_screen_menu.cpp)
Game top menu text now goes through localisation lookup
Added English localisation of game top menu text
Fixed no newline at end of file on .gitignore and en.po
Added tooltips to game top menu population, currency and date areas, as in real Caesar 3
Added tooltips to game side menu overlays button and min/maximize buttons
Added tooltips to info game buttons