Document new features and update examples throughout docs

[TheRealPear]

First pull request of the year to fix examples throughout the docs as well as documenting new PGM features. For convenience, I've put them in the form of check boxes with a link to the relevant issue or pull request from other PGM repositories.

• Update example maps with XML changes. These maps were already using 1.4.2, but I wanted to bring over the changes I made in the linked pull request. (Update sample maps for proto 1.4.2 Maps#1)
• Update pre-existing XML blocks to use 1.4.2 syntax (see Structures, Classes, Items, Kits, Projectiles, Main Map Element, Filters, Portals, Regions, Spawns, Control Points, Capture the Wool, Other Objectives, and Scoring)
• Document actions in kill rewards module (Improve killrewards, support action & victim action PGM#1251)
• Document variant <if>/<unless> conditional attributes (Variant improvements in pools & map command PGM#1250)
• Document constant delete attribute (Add support for deleting nodes with constants PGM#1256)
• Update offset filter section (Dynamic offset filter PGM#1262)
• Add a section on inline filters in Filters page (Document Inline Filters #99 Implement PoC inline filters PGM#1106 Implement parser for inline filters PGM#1257)
• Document exclusive attribute in dummy variables (Implement exclusive attribute on dummy variables PGM#1245)
• Document score, with-team, and lives variable (Add Score & team-rescoping variables PGM#1220)

Please comment if I have missed any PGM features that was recently added that is yet to be documented on pgm.dev

[TheRealPear]

Documented more details about proto 1.3.0 region max bug, offset filter changes, exclusive attribute, and new variables.

[TheRealPear]

Everything has been checked off and reviewed with Pablo

[TheRealPear]

• Clarified more on module id and variable id limitations
• Added {0} example to countdown, after, and pulse filter section
• Changed variable examples to use underscore instead of dash for its ids