Squashed 'sqscripter/' content from commit ae07f47

git-subtree-dir: sqscripter
git-subtree-split: ae07f47a16d921830b4ff4cc90486c2c2af954b9
Merge commit '591262d93d65d3f40b8fc5d840e3637bb9a60fe9' as 'sqscripter'
Adapt to sqscripter project (modified SciLexer.DLL)
Adapt to Squirrel syntax coloring in SqScripter
Show compile errors in Squirrel scripts to SqScripter window
Show Squirrel runtime errors in SqScripter window

Now it can show source file and position where an error has occurred,
which helps debugging greatly.