Replace bare 'except:' with 'except Exception:' (#281)

Catching all exceptions is generally considered a bad practice under
most circumstances as it will also catch KeyboardInterrupt and
SystemExit. These special cases should be raised to the interpreter to
allow the Python process to exit.

This fix complies with pycodestyle's error code E722:

https://pycodestyle.readthedocs.io/en/latest/intro.html#error-codes

> do not use bare except, specify exception instead

src/icalendar/parser.py

@@ -391,7 +391,7 @@ class Contentlines(list):
                         line in NEWLINE.split(unfolded) if line)
             lines.append('')  # '\r\n' at the end of every content line
             return lines
-        except:
+        except Exception:
             raise ValueError('Expected StringType with content lines')
 
 

src/icalendar/prop.py

@@ -174,7 +174,7 @@ class vBoolean(int):
     def from_ical(cls, ical):
         try:
             return cls.BOOL_MAP[ical]
-        except:
+        except Exception:
             raise ValueError("Expected 'TRUE' or 'FALSE'. Got %s" % ical)
 
 
@@ -213,7 +213,7 @@ class vFloat(float):
     def from_ical(cls, ical):
         try:
             return cls(ical)
-        except:
+        except Exception:
             raise ValueError('Expected float value, got: %s' % ical)
 
 
@@ -232,7 +232,7 @@ class vInt(int):
     def from_ical(cls, ical):
         try:
             return cls(ical)
-        except:
+        except Exception:
             raise ValueError('Expected int, got: %s' % ical)
 
 
@@ -371,7 +371,7 @@ class vDate(object):
                 int(ical[6:8]),  # day
             )
             return date(*timetuple)
-        except:
+        except Exception:
             raise ValueError('Wrong date format %s' % ical)
 
 
@@ -437,7 +437,7 @@ class vDatetime(object):
                 return pytz.utc.localize(datetime(*timetuple))
             else:
                 raise ValueError(ical)
-        except:
+        except Exception:
             raise ValueError('Wrong datetime format: %s' % ical)
 
 
@@ -492,7 +492,7 @@ class vDuration(object):
             if sign == '-':
                 value = -value
             return value
-        except:
+        except Exception:
             raise ValueError('Invalid iCalendar duration: %s' % ical)
 
 
@@ -557,7 +557,7 @@ class vPeriod(object):
             start = vDDDTypes.from_ical(start)
             end_or_duration = vDDDTypes.from_ical(end_or_duration)
             return (start, end_or_duration)
-        except:
+        except Exception:
             raise ValueError('Expected period format, got: %s' % ical)
 
     def __repr__(self):
@@ -598,7 +598,7 @@ class vWeekday(compat.unicode_type):
     def from_ical(cls, ical):
         try:
             return cls(ical.upper())
-        except:
+        except Exception:
             raise ValueError('Expected weekday abbrevation, got: %s' % ical)
 
 
@@ -631,7 +631,7 @@ class vFrequency(compat.unicode_type):
     def from_ical(cls, ical):
         try:
             return cls(ical.upper())
-        except:
+        except Exception:
             raise ValueError('Expected frequency, got: %s' % ical)
 
 
@@ -705,7 +705,7 @@ class vRecur(CaselessDict):
                     continue
                 recur[key] = cls.parse_type(key, vals)
             return dict(recur)
-        except:
+        except Exception:
             raise ValueError('Error in recurrence rule: %s' % ical)
 
 
@@ -754,7 +754,7 @@ class vTime(object):
         try:
             timetuple = (int(ical[:2]), int(ical[2:4]), int(ical[4:6]))
             return time(*timetuple)
-        except:
+        except Exception:
             raise ValueError('Expected time, got: %s' % ical)
 
 
@@ -775,7 +775,7 @@ class vUri(compat.unicode_type):
     def from_ical(cls, ical):
         try:
             return cls(ical)
-        except:
+        except Exception:
             raise ValueError('Expected , got: %s' % ical)
 
 
@@ -788,7 +788,7 @@ class vGeo(object):
             latitude, longitude = (geo[0], geo[1])
             latitude = float(latitude)
             longitude = float(longitude)
-        except:
+        except Exception:
             raise ValueError('Input must be (float, float) for '
                              'latitude and longitude')
         self.latitude = latitude
@@ -803,7 +803,7 @@ class vGeo(object):
         try:
             latitude, longitude = ical.split(';')
             return (float(latitude), float(longitude))
-        except:
+        except Exception:
             raise ValueError("Expected 'float;float' , got: %s" % ical)
 
 
@@ -853,7 +853,7 @@ class vUTCOffset(object):
                                              int(ical[3:5]),
                                              int(ical[5:7] or 0))
             offset = timedelta(hours=hours, minutes=minutes, seconds=seconds)
-        except:
+        except Exception:
             raise ValueError('Expected utc offset, got: %s' % ical)
         if not cls.ignore_exceptions and offset >= timedelta(hours=24):
             raise ValueError(