plugin linewrapping: added priority

Since the linewrapping plugin modifies some of the DocView line
calculation and positioning functions we need to make sure of loading it
before other plugins. This way we make sure that plugins that also overwrite
and depend on DocView functionality aren't using the original methods without
the linewrapping changes, which leads to wrong line and column calculations.

data/plugins/linewrapping.lua

@@ -1,4 +1,4 @@
--- mod-version:3
+-- mod-version:3 --priority:10
 local core = require "core"
 local common = require "core.common"
 local DocView = require "core.docview"