Fix scale terminology (minimum/maximum/small/large/big scale)

[havatv]

A while ago, DENOM was appended to the SCALE tags (...SCALEDENOM) to make mapserver terminology consistent with mapping terminology. However, there are still som inconsistencies in the terminology related to scale in the tag explanations.

I think we should fix these. Here are some examples:

MAXSCALEDENOM - change maximum scale to minium scale, and bigger scale to smaller scale
MINSCALEDENOM - change minimum scale to maximum scale, and smaller scale to larger scale
MAXSCALE - change maximum scale to minium scale, and bigger scale to smaller scale
MINSCALE - change minimum scale to maximum scale, and smaller scale to larger scale
MAXTEMPLATE - change above the maximum scale to below the minium scale + added explanation
MINTEMPLATE - change above the minimum scale to above the maximum scale + added explanation

Layer tags:
MAXSCALEDENOM - change maximum scale to minium scale
MINSCALEDENOM - change minimum scale to maximum scale
MAXSCALE - change maximum scale to minium scale
MINSCALE - change minimum scale to maximum scale
LABELMAXSCALEDENOM - change maximum scale to minium scale
LABELMINSCALEDENOM - change minimum scale to maximum scale
LABELMAXSCALE - change maximum scale to minium scale
LABELMINSCALE - change minimum scale to maximum scale

Class tags:
MAXSCALEDENOM - change maximum scale to minium scale
MINSCALEDENOM - change minimum scale to maximum scale
MAXSCALE - change maximum scale to minium scale
MINSCALE - change minimum scale to maximum scale