-- various functions for construction parameter handling. Extends the default paramutil

function paramsutil.replaceParam(key, value, params)
-- removes the parameter with key="key" from params and adds the supplied params from "value"
-- "key" = key name of the parameter
-- "value" = a parameter strcture or a table of parameter structures
-- "params" = your local params that will be modified

function paramsutil.paramValue(pkey,pname,pvalues,pyearFrom,pyearTo)
-- generic parameter build from an array
-- "pkey" = parameter key
-- "pname" = parameter name to be displayed
-- "pvalues" = a table of values to be chosen from
-- "pyearFrom" = starting game year when the parameter will be displayed (0 - from the game start)
-- "pyearTo" = ending game year when the parameter will be hidded (0 - forever)

function paramsutil.paramCatenary()
-- track catenary param. gets the track catenary availability year from game configuration

function paramsutil.paramTrackType(params,keyname,name)
-- adds track type parameter depending on years of availability. the tracks are those loaded by TrackLib
-- "params" = your local params that will be modified
-- "keyname" optional = parameter keyname. defaults to "trackType"
-- "name" optional = display name. defaults to "Track type"

function paramsutil.getSelectedTrackType(params,keyname)
-- returns data of the selected track as a table like:
-- {
--		filename="mytrack.lua"
--		data={ -- track data as added by track mods
--			name="MyTrack",
--			speedLimit=120,
--			...
--		}
-- {
-- "params" = your params as received by updateFn(params)
-- "keyname" optional = parameter keyname. defaults to "trackType"


