Configurable item description, native-looking ilvl/alvl display

[youbetterdont]

Original

This feature adds a configurable item description that the user can set through BH.cfg. The syntax is as follows:

ItemDisplay[blah]: %NAME%{my description}

The description field can tell players more about items they pick up due to a notification (e.g., in a default config). It can also give relevant cube recipes, possible runewords, etc. The description is only displayed on the item if "Advanced Item Display" is active.

Here's an example that adds description text to a Titan's Revenge.

Because much of the code that controls item name display was reused, many of the same features still work. That is, all keywords like colors, etc. are supported. Even the %NAME% directive still has meaning. For example:

The above example shows that %CONTINUE% still applies as before. However, when %NAME% is used in the description field, it uses the last set description, not the item name.

If no %CONTINUE% is used, the behavior is as expected:

Here's an example showing that the %ILVL% keyword still works in the description field:

This PR also adds support for more native looking item level and affix level display. You can see the item level display above. Similarly, affix level is shown for magic, rare, and crafted quality items. Affix level is only shown if it is different than item level. Additionally, the user must set "Advanced Item Display" and "Show iLvl" for these features to be active. Here is the affix level display on some rare gloves:

Update 3/25

• Description rule list is now separate from the main one. This allows for setting descriptions separate from item names, e.g.

ItemDisplay[blah]: %NAME%
ItemDisplay[blah]: {description}

• Tweak item rules slightly so that more conditions are required to create an ignore rule. Before, an ignore rule would be created in the following situations.

ItemDisplay[blah]: %MAP%
ItemDisplay[blah]: %NAME%

The above previously resulted in a blank item name. The item was not blocked because of the `%MAP% command, but still this is probably not desirable behavior. After this fix, the item name will no longer be blank.

ItemDisplay[blah]: %CONTINUE%
ItemDisplay[blah]: %NAME%

The above would also result in a blank item name. Additionally, the item will be blocked in this case. After the fix, the item name is preserved, and no ignore rule is created. This is kind of a corner case, but I think this is the more desirable behavior.

• After this fix, an ignore rule is only created when the item name and description are not blank, there is no map action, and there is no %CONTINUE% statement. Essentially only blank lines can create ignore rules now.
• Blank item names should no longer be generated as a result of the above changes. To warn users that an item they see in game will be blocked by the packet filter, a [blocked] tag is added to the item. For example:
  
  The blocked tag is only generated when the item has an ignore rule and not a map rule. This change also fixes some other undesirable behavior.

ItemDisplay[blah]: %NAME%%MAP%%CONTINUE%
ItemDisplay[blah]: 

Previously, the above would result in a blank item name, but the item would still spawn in game and ping. After the fix, the item name will no longer be blank. The item will ping as before.

[youbetterdont]

Included in #50