Weapons can now have the "double_weapon" property to enable two handed weapons to count as dual wielding

made dual archery range not sutpid

Arcane Shield fix

Allow damage shields to merge

-This change was originally intended to fix a bug with Arcane Shield
(http://forums.te4.org/viewtopic.php?f=42&t=44895), but I ended up
creating an on_merge function for timed effect DAMAGE_SHIELD so now
anything that creates damage shields will intelligently overwrite an
existing shield.

-Will replace an existing damage shield entirely if both the shield
value and duration would be greater on the new shield.

-Will update the current shield value (but not max value) of an
existing shield if the new value would be greater. We keep the old
max value because the player may want to buff their shield with Aegis.

-If we updated an existing shield, we will refresh the current duration
based on the new shield's duration unless the duration has already been
refreshed 20 times. This checks the same property used by Weapon of
Light and Bathe in Light, which is why I allowed refreshing 20 times
instead of a smaller amount.

-Will never update or replace an existing shield if the
current duration is greater than the new shield's duration. We
can't know whether the player values shield value or duration more, and
updating the shield value of an existing damage shield with greater
duration would introduce power creep.

-Will never merge a reflection shield with a normal shield. For merging
two reflection shields, the lesser reflect value is used.

-Many shield sources (e.g., Shielding rune) are still disabled while
the player has a damage shield. This is fine because the player can
always cancel the current effect if they want to replace it. For
merging, we're mainly concerned about back-end sources like Arcane
Shield.

-EFF_DAMAGE_SHIELD and EFF_PSI_DAMAGE_SHIELD replace each other upon
activation (existing behavior). I may address that in a different
branch, but I need to investigate the consequences of changing it.

Others work incorporated

Little bit of astralInferno and Marson's code, again.

Merge branch 'MinimalistColors' of http://git.net-core.org/Hachem_Muche/t-engine4 into Hachem_Muche/t-engine4-MinimalistColors

Conflicts:
	game/modules/tome/data/resources.lua

Expose default resource shader params to the "UISet:Minimalist:Load" hook
Color priority is resource_definition.Minimalist.shader_params.color > Minimalist.shader_params[resource].color > resource_definition.color

-Will replace an existing damage shield entirely if both the shield
value and duration would be greater on the new shield.
-Will update the current shield value (but not max value) of an
existing shield if the new value would be greater. We keep the old
max value because the player may want to buff their shield with Aegis.
-If we updated an existing shield, we will refresh the duration to
3 turns unless the duration has already been refresh 20 times. This
checks the same property used by Weapon of Light and Bathe in Light,
which is why I allowed refreshing 20 times instead of a smaller amount.
-It's unlikely that an existing shield would be refreshed many times by
Arcane Shield, but I implemented this limitation to avoid refreshing
the same shield indefinitely. T think Aegis is the only talent that
benefits from refreshing an existing shield versus creating a new one,
so there shouldn't be any real abuse potential here.
-Note that this will never update or replace an existing shield if the
current duration is greater than Arcane Shield's default duration. We
can't know whether the player values shield value or duration more, and
updating the shield value of an existing damage shield with greater
duration would introduce power creep.