Fix problem with static renderings

The issue was that rendertiddlers always clears the output folder,
which meant that it was overwriting anything previously output by the
rendertiddler command.

bld.cmd

@@ -45,8 +45,8 @@ node .\tiddlywiki.js ^
 	--savetiddler $:/green_favicon.ico %TW5_BUILD_OUTPUT%/static/favicon.ico ^
 	--rendertiddler $:/core/templates/static.template.html static.html text/plain ^
 	--rendertiddler $:/core/templates/alltiddlers.template.html alltiddlers.html text/plain ^
-	--rendertiddler $:/core/templates/static.template.css static\static.css text/plain ^
 	--rendertiddlers [!is[system]] $:/core/templates/static.tiddler.html static text/plain ^
+	--rendertiddler $:/core/templates/static.template.css static\static.css text/plain ^
 	|| exit 1
 
 rem encrypted.html: a version of the main file encrypted with the password "password"

bld.sh

@@ -46,8 +46,8 @@ node ./tiddlywiki.js \
 	--savetiddler $:/green_favicon.ico static/favicon.ico \
 	--rendertiddler $:/core/templates/static.template.html static.html text/plain \
 	--rendertiddler $:/core/templates/alltiddlers.template.html alltiddlers.html text/plain \
-	--rendertiddler $:/core/templates/static.template.css static/static.css text/plain \
 	--rendertiddlers [!is[system]] $:/core/templates/static.tiddler.html static text/plain \
+	--rendertiddler $:/core/templates/static.template.css static/static.css text/plain \
 	|| exit 1
 
 # encrypted.html: a version of the main file encrypted with the password "password"

editions/tw5.com/tiddlers/howtos/Notes for upgrading to 5.0.11-beta.tid

@@ -21,3 +21,5 @@ You can override this behaviour with the OutputCommand. For example, to generate
 ```
 tiddlywiki mywiki --output . --rendertiddler $:/core/save/all index.html text/plain
 ```
+
+A further change is that the `--rendertiddlers` command now clears the output folder before it writes any files. This means that any previous `--rendertiddler` commands to the same folder will have their output deleted.

editions/tw5.com/tiddlywiki.info

@@ -48,8 +48,8 @@
 		"static": [
 			"--rendertiddler","$:/core/templates/static.template.html","static.html","text/plain",
 			"--rendertiddler","$:/core/templates/alltiddlers.template.html","alltiddlers.html","text/plain",
-			"--rendertiddler","$:/core/templates/static.template.css","static/static.css","text/plain",
-			"--rendertiddlers","[!is[system]]","$:/core/templates/static.tiddler.html","static","text/plain"]
+			"--rendertiddlers","[!is[system]]","$:/core/templates/static.tiddler.html","static","text/plain",
+			"--rendertiddler","$:/core/templates/static.template.css","static/static.css","text/plain"]
 	},
 	"config": {
 		"retain-original-tiddler-path": true