Unable to compile examples as instructed with 'nake'.
Tried to compile the examples but hit exceptions:
```
$ nake
Compiling nakefile...
No task specified, running default task defined by nakefile.
Warning: icon was not found: build\windows\res\MyGame.ico
Hint: used config file 'C:\msys64\mingw64\etc\nim\nim.cfg' [Conf]
Hint: used config file 'C:\msys64\mingw64\etc\nim\config.nims' [Conf]
...................................................................................................
C:\msys64\home\ANDREWG\nimx\nimx\private\font\fontconfig.nim(3, 20) Warning: imported and not used: 'strutils' [UnusedImport]
C:\msys64\home\ANDREWG\nimx\nimx\private\font\fontconfig.nim(3, 12) Warning: imported and not used: 'dynlib' [UnusedImport]
..............
C:\msys64\home\ANDREWG\nimx\nimx\layout_vars.nim(19, 32) Error: type mismatch: got <Variable>
but expected one of:
proc newExpression(constant: float = 0): Expression
  first type mismatch at position: 1
  required type for constant: float
  but expression 'left(phs)' is of type: Variable
proc newExpression(term: Term; constant: float = 0): Expression
  first type mismatch at position: 1
  required type for term: Term
  but expression 'left(phs)' is of type: Variable
proc newExpression(terms: seq[Term]; constant: float = 0): Expression
  first type mismatch at position: 1
  required type for terms: seq[Term]
  but expression 'left(phs)' is of type: Variable

expression: newExpression(left(phs))
```
------------------------------------------------------
Using MINGW64, Nim Compiler Version 1.4.6 [Windows: amd64]