[FIX] hw_*: do not install the posbox modules

These modules are currently made to run with an odoo 8.0 server.
They are given as-it on the odoo repository but are intended to be run on the
posbox and not supported on a classic server.

addons/hw_blackbox_be/__manifest__.py

@@ -20,4 +20,5 @@ Data Module but will not modify the behaviour of the Point of Sale.
 """,
     'depends': ['hw_proxy'],
     'external_dependencies': {'python': ['serial']},
+    'installable': False,
 }

addons/hw_escpos/__manifest__.py

@@ -20,4 +20,5 @@ that would need such functionality.
     'external_dependencies': {
         'python' : ['usb.core','serial','qrcode'],
     },
+    'installable': False,
 }

addons/hw_proxy/__manifest__.py

@@ -17,4 +17,5 @@ This modules only contains the enabling framework. The actual devices drivers
 are found in other modules that must be installed separately. 
 
 """,
+    'installable': False,
 }

addons/hw_scale/__manifest__.py

@@ -17,4 +17,5 @@ such as the Mettler Toledo Ariva.
 """,
     'depends': ['hw_proxy'],
     'external_dependencies': {'python': ['serial']},
+    'installable': False,
 }

addons/hw_scanner/__manifest__.py

@@ -18,4 +18,5 @@ point of sale module.
 """,
     'depends': ['hw_proxy'],
     'external_dependencies': {'python': ['evdev']},
+    'installable': False,
 }