validate link only if value is non empty
diff --git a/public/js/all-app.js b/public/js/all-app.js
index 68dca2f..6e2fa3e 100644
--- a/public/js/all-app.js
+++ b/public/js/all-app.js
@@ -746,7 +746,7 @@
 if(cur_frm){if(val==locals[me.doctype][me.docname][me.df.fieldname]){me.run_trigger();return;}}
 me.set(val);if(_f.cur_grid_cell)
 _f.cur_grid_cell.grid.cell_deselect();if(locals[me.doctype][me.docname][me.df.fieldname]&&!val){me.run_trigger();return;}
-me.validate_link(val,from_selector);}
+if(val){me.validate_link(val,from_selector);}}
 LinkField.prototype.validate_link=function(val,from_selector){var me=this;var fetch='';if(cur_frm.fetch_dict[me.df.fieldname])
 fetch=cur_frm.fetch_dict[me.df.fieldname].columns.join(', ');$c('webnotes.widgets.form.utils.validate_link',{'value':val,'options':me.df.options,'fetch':fetch},function(r,rt){if(r.message=='Ok'){if($(me.txt).val()!=val){if((me.grid&&!from_selector)||(!me.grid)){$(me.txt).val(val);}}
 if(r.fetch_values)
@@ -1572,7 +1572,7 @@
 if(cur_frm){if(val==locals[me.doctype][me.docname][me.df.fieldname]){me.run_trigger();return;}}
 me.set(val);if(_f.cur_grid_cell)
 _f.cur_grid_cell.grid.cell_deselect();if(locals[me.doctype][me.docname][me.df.fieldname]&&!val){me.run_trigger();return;}
-me.validate_link(val,from_selector);}
+if(val){me.validate_link(val,from_selector);}}
 LinkField.prototype.validate_link=function(val,from_selector){var me=this;var fetch='';if(cur_frm.fetch_dict[me.df.fieldname])
 fetch=cur_frm.fetch_dict[me.df.fieldname].columns.join(', ');$c('webnotes.widgets.form.utils.validate_link',{'value':val,'options':me.df.options,'fetch':fetch},function(r,rt){if(r.message=='Ok'){if($(me.txt).val()!=val){if((me.grid&&!from_selector)||(!me.grid)){$(me.txt).val(val);}}
 if(r.fetch_values)
@@ -2288,7 +2288,7 @@
    onclick="return false;">Help<b class="caret"></b></a>\
   <ul class="dropdown-menu" id="toolbar-help">\
   </ul></li>')
-$('#toolbar-help').append('<li><a href="http://erpnext.blogspot.com/2011/03/erpnext-help.html" target="_blank">\
+$('#toolbar-help').append('<li><a href="https://erpnext.com/manual" target="_blank">\
   Documentation</a></li>')
 $('#toolbar-help').append('<li><a href="http://groups.google.com/group/erpnext-user-forum" target="_blank">\
   Forum</a></li>')
diff --git a/public/js/fields.js b/public/js/fields.js
index b9dca90..32aa00c 100644
--- a/public/js/fields.js
+++ b/public/js/fields.js
@@ -110,7 +110,7 @@
 if(cur_frm){if(val==locals[me.doctype][me.docname][me.df.fieldname]){me.run_trigger();return;}}
 me.set(val);if(_f.cur_grid_cell)
 _f.cur_grid_cell.grid.cell_deselect();if(locals[me.doctype][me.docname][me.df.fieldname]&&!val){me.run_trigger();return;}
-me.validate_link(val,from_selector);}
+if(val){me.validate_link(val,from_selector);}}
 LinkField.prototype.validate_link=function(val,from_selector){var me=this;var fetch='';if(cur_frm.fetch_dict[me.df.fieldname])
 fetch=cur_frm.fetch_dict[me.df.fieldname].columns.join(', ');$c('webnotes.widgets.form.utils.validate_link',{'value':val,'options':me.df.options,'fetch':fetch},function(r,rt){if(r.message=='Ok'){if($(me.txt).val()!=val){if((me.grid&&!from_selector)||(!me.grid)){$(me.txt).val(val);}}
 if(r.fetch_values)