Patch v1.51 file

Patch v1.51 information

Bug fixes:
- Fixed a bug that caused range check error in tactical battles
- Fixed a bug that caused range check error on the strategic map
- Fixed a bug that caused leaders to be replaced by grey figures
- Fixed a PBEM bug when recruiting

Enhancements:
- Explanation added when you cannot fire in battles
- Explanation / hint added to some context menu items
- Explanation added when you cannot recruit a unit type
- Units under 40 morale will not be able to charge (applied to auto battles as well)
- Raised melee casualties a bit - this will be revised completely in a future patch
- Americans will not be able to request weapons and guns before the French aid event