bootstrap: Generate final install.sh during build

This solves problem where bootstrap was simply copying ./install.sh.template
into ./install.sh. Then first call of ./install.sh was calling ./koch install
that was running extra compilation and overwriting ./install.sh with new
content.

This was overcomplicated, and also caused first `sudo ./install.sh DIR` to run
compilation under root account, leaving root owned files in working directory.

Now bootstrap calls `./koch geninstall` that just generates ./install.sh
without calling it. This ./install.sh is FINAL one, and running it does not
generate any files aside passed DIR. This makes whole process simpler.

bootstrap.sh

@@ -12,8 +12,11 @@ cd ".."
 
 ./bin/nim c koch
 ./koch boot -d:release
+./koch geninstall
 
-cp -f install.sh.template install.sh
+set +x
-chmod +x install.sh
+
+echo
+echo 'Install Nim using "./install.sh <dir>" or "sudo ./install.sh <dir>".'
 
 exit 0

install.sh.template

@@ -1,9 +0,0 @@
-#!/bin/sh
-set -e
-set -x
-
-if [ "$1" != "" ]; then
-	exec ./koch install "$1"
-else
-	exec ./koch install
-fi