bootstraps works again; get rid of compile-time 'rand' (too weird)

compiler/ast.nim

@@ -549,7 +549,7 @@ type
     mFields, mFieldPairs, mOmpParFor,
     mAppendStrCh, mAppendStrStr, mAppendSeqElem,
     mInRange, mInSet, mRepr, mExit, mSetLengthStr, mSetLengthSeq,
-    mIsPartOf, mAstToStr, mRand,
+    mIsPartOf, mAstToStr, mParallel,
     mSwap, mIsNil, mArrToSeq, mCopyStr, mCopyStrLast,
     mNewString, mNewStringOfCap,
     mReset,
@@ -600,7 +600,6 @@ const
     mConTArr, mConTT,
     mAppendStrCh, mAppendStrStr, mAppendSeqElem, 
     mInRange, mInSet, mRepr,
-    mRand, 
     mCopyStr, mCopyStrLast}
   # magics that require special semantic checking and
   # thus cannot be overloaded (also documented in the spec!):
@@ -873,7 +872,7 @@ const
     skMacro, skTemplate, skConverter, skEnumField, skLet, skStub}
   PersistentNodeFlags*: TNodeFlags = {nfBase2, nfBase8, nfBase16,
                                       nfDotSetter, nfDotField,
-                                      nfAllConst,nfIsRef}
+                                      nfIsRef}
   namePos* = 0
   patternPos* = 1    # empty except for term rewriting macros
   genericParamsPos* = 2

lib/system.nim

@@ -2719,9 +2719,6 @@ proc `/=`*[T: float|float32|float64] (x: var T, y: T) {.inline, noSideEffect.} =
 
 proc `&=`* (x: var string, y: string) {.magic: "AppendStrStr", noSideEffect.}
 
-proc rand*(max: int): int {.magic: "Rand", sideEffect.}
-  ## compile-time `random` function. Useful for debugging.
-
 proc astToStr*[T](x: T): string {.magic: "AstToStr", noSideEffect.}
   ## converts the AST of `x` into a string representation. This is very useful
   ## for debugging.