Update to CodeMirror 4.2
Use CodeMirror 4.2 dir
Rename function doFold and new namespace

doFold seems a better name, so renamed and rangeFinder var now foldType
New namespace convention on folding, also specifying type by foldType
Use doFold now, pass string instead of object
setLine now replaceRange, around on getSelection

setLine deprecated, now need to use replaceRange and pass 2 objects for
start & end (line & ch)
getSelection needs "around" param as default is now "end"
onkeyup own event now and fold changes

onKeyEvent is no longer a param function, now something set in an 'on'
event function
setLine now replaceRange
doFold is the new fold function, "brace" or "xml" string passed to it,
not an object now
codeFoldTag and codeFoldBrace vars no longer needed now
Changes to fit in with CodeMirror 4.2

setLine is now replaceRange
New namespacing on folding
replaceSelection needs "around" param
removeLine deprecated, using execCommand('deleteLine') now
cursor.end set to 1000000 for consistency