Numbers with a fixed field width/precision are not parsed properly

[rgeorgiev583]

There are several issues with the parsing of numeric fields with a fixed width and/or precision. The common pattern for all of them is that the width/precision specification is applied inconsistently for different numeric representations (i.e. decimal, hexadecimal, etc):

>>> from parse import parse

>>> parse("#{:2.2x}{:2.2x}{:2.2x}", "#FFFFFF")
<Result (65535, 15, 15) {}>
>>> parse("#{:2.2x}{:2.2x}{:2.2x}", "#FFFF")
<Result (255, 15, 15) {}>
>>> parse("#{:2.2x}{:2.2x}{:2.2x}", "#FFF")
<Result (15, 15, 15) {}>
>>> parse("{:2.2d}{:2.2d}{:2.2d}", "9999")
<Result (99, 9, 9) {}>
>>> parse("{:2.2d}{:2.2d}{:2.2d}", "999")
<Result (9, 9, 9) {}>

As per the documentation: Width specifies a minimum size and precision specifies a maximum. In all of the cases, we both have a width and a precision field. However, in the first case the parsing of the first number field consumes four hexadecimal digits despite the fact that the precision should specify a maximum field length. What is more, we also have a width specifier which says that the numbers should be at least two digits long, and yet the latter two numbers are represented using only one digit. The rest of the cases demonstrate the same issue with the width specifier.

[r1chardj0n3s]

This is quite likely related to #99