Little improvements in JsTemplate.js.
Added new features to JsTemplate.js.

The following functions are now available for use in template code:
 - ParseJsonFile
 - ReplaceInNextLine
 - ReplaceIdentifierInNextLine
 - PushReplace
 - PushReplaceIdentifier
 - PopReplace
 - ResetReplaces

Theese new functions mostly deal with replacements in template text.
More detailed documentation will be available later.