Two syntax coloring issues

[dwhall]

1. A number in scientific notation does not colorize completely when 'E' is used for the exponent.

let v1 = 6e23   # good
let v2 = 6E23   # 6 is colored, E23 is not

2. Custom numeric literal does not colorize properly

type Foo* = distinct uint32

func parseAnyInt(s: static string): int =
  const lowercase = toLower(s)
  when lowercase.startsWith("0x") or lowercase.startsWith("-0x"):
    parseHexInt(lowercase)
  else:
    parseInt(s)

func `'foo`*(s: static string): Foo =
  const n = parseAnyInt(s)
  Foo(n)

func `'bar`*(s: static string): Foo =
  const n = parseAnyInt(s)
  Foo(n)

let f1 = 0x41'foo   # foo is white
let f2 = 0x42'bar   # bar is red
let f3 = -0x43'bar  # wonky until the apostrophe