(a) When any period of time is referred to in any rule, such period in all cases, except as otherwise provided in Rules 107 and 108, shall be so computed as to exclude the first and include the last day of such period.(b) Whenever the last day of any such period shall fall on Saturday or Sunday, or on any day made a legal holiday by the laws of this Commonwealth or of the United States, such day shall be omitted from the computation.
