bump a version

Author: bobzhang

jscomp/common/bs_version.ml

@@ -22,7 +22,7 @@
  * You should have received a copy of the GNU Lesser General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)    
-let version = "8.3.0-dev.2"
+let version = "8.4.0-dev.1"
 let header = 
    "// Generated by ReScript, PLEASE EDIT WITH CARE"  
 let package_name = "bs-platform"   

lib/4.06.1/bsb.ml

@@ -55,7 +55,7 @@ end = struct
  * You should have received a copy of the GNU Lesser General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)    
-let version = "8.3.0-dev.2"
+let version = "8.4.0-dev.1"
 let header = 
    "// Generated by ReScript, PLEASE EDIT WITH CARE"  
 let package_name = "bs-platform"   

lib/4.06.1/unstable/js_compiler.ml

@@ -17876,7 +17876,7 @@ end = struct
  * You should have received a copy of the GNU Lesser General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)    
-let version = "8.3.0-dev.2"
+let version = "8.4.0-dev.1"
 let header = 
    "// Generated by ReScript, PLEASE EDIT WITH CARE"  
 let package_name = "bs-platform"   

lib/4.06.1/unstable/js_refmt_compiler.ml

@@ -17876,7 +17876,7 @@ end = struct
  * You should have received a copy of the GNU Lesser General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)    
-let version = "8.3.0-dev.2"
+let version = "8.4.0-dev.1"
 let header = 
    "// Generated by ReScript, PLEASE EDIT WITH CARE"  
 let package_name = "bs-platform"   

lib/4.06.1/whole_compiler.ml

@@ -304348,7 +304348,7 @@ end = struct
  * You should have received a copy of the GNU Lesser General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)    
-let version = "8.3.0-dev.2"
+let version = "8.4.0-dev.1"
 let header = 
    "// Generated by ReScript, PLEASE EDIT WITH CARE"  
 let package_name = "bs-platform"   

package.json

@@ -18,7 +18,7 @@
     "coverage": "nyc --timeout=3000 --reporter=html mocha jscomp/test/*test.js && open ./coverage/index.html"
   },
   "name": "bs-platform",
-  "version": "8.3.0-dev.2",
+  "version": "8.4.0-dev.1",
   "description": "ReScript compiler, OCaml standard libary by ReScript and its required runtime support",
   "repository": {
     "type": "git",