[FIX] translate: allow common english 2 chars terms

Before, all isolated (between xml/html tags) two chars words coming from views were not translated (by choice).
But, for some words, allowing them is useful. For instance, the word 'or' located between two buttons.

opw-616716

openerp/tools/translate.py

@@ -137,6 +137,9 @@ _LOCALE2WIN32 = {
 
 }
 
+# These are not all english small words, just those that could potentially be isolated within views
+ENGLISH_SMALL_WORDS = set("as at by do go if in me no of ok on or to up us we".split())
+
 
 class UNIX_LINE_TERMINATOR(csv.excel):
     lineterminator = '\n'
@@ -676,7 +679,7 @@ def trans_generate(lang, modules, cr):
 
     def push(mod, type, name, res_id, term):
         term = (term or '').strip()
-        if len(term) > 2:
+        if len(term) > 2 or term in ENGLISH_SMALL_WORDS:
             push_translation(mod, type, name, res_id, term)
 
     def get_root_view(xml_id):