Fixed a bug in Map::checkSightLine.

The sight is not neccesarily clear because x and y coordinates match, z
needs to be checked too.
Fixed a bug with variantToPosition.
Unimportant fix: removed a duplicated line at global.lua.
1) Added the executable bit at the autogen.sh file.
2) Fixed a small bug with makefile which was causing config.lua not being automatically copied into src directory.
1) Fixed codeblocks project. 2) Removal of some annoying warning messages.
More fixes for the codeblock project file.
Config.lua file now works with case sensitive file systems (guys, let's keep in mind that not everyone use windows).
As now we only have one data directory, it makes sense to move back the data directory into the src directory.
This commit is mainly about introducing Lua functions to allow more powerful scripts.  1) All LuaScriptInterface::getField functions now give the programmer (sourcecode) the possibility to check for missing values; 2) Now distance of target as well as the range of distance attacks is a dynamic variable and can be controlled by the Lua scripter; 3) Added some Lua functions allowing very advanced (and probably not useful for most scripters) management of fields and conditions; 4) Added some Lua functions giving more information about itemtypes (getItemBreakChance, getItemShootRange and etc) and some miscelaneous functions (getAllItems); 5) Added a more powerful version of doTargetCombatHealth(no support for callbacks).
Added the global_list_interface, a basic and not very polite (althought handy) workaround for situations in which you need to share a variable between different Lua environments (for example, an onLogin script and an onUse script).
Removed one warning message (I forgot to erase a line at the previous commit).
Fixed some cases of violation of aliasing rules, as it might cause some undefined behavior and therefore may cause unexpected issues at some compilers (by doing that, we have also removed several warning messages.
Corrected the fact that events onGetPlayerMinMaxValues were using the value 7 for any fist attack. Now it uses the value in config.lua for fist_strenght, as it should be.
Unimportant formatting changes.
At a previous recent commit, I have accidentaly changed the type of return of PeekU32 to uint16_t, which was messing up everything (it was not even possible to login at the server). This commit solves this issue and also change unimportant things.
As skilltries are uint64_t since revision 6233, the cache also must be uint64_t.
Added variant types to global.lua.
Renamed the build directory. We better reserve the name 'build' specifically for the output directory of premake.
Fixed a small bug with getLastDamageConditionValue.
Fixed an error at the previous commit.