Support arbitrary code lengths. Fixes #11.

[JackZielke]

Support code lengths other than 6.

When adding codes, the default is 6 digits unless otherwise specified. Max length is 10.* This bumps the version since the config page is incompatible with the old version. The new code needs the code lengths and the new config page provides them. I have not tested the old app with the new config page. I expect the old code to ignore the lengths and still work.

PR https://github.com/cpfair/pTOTP/pull/6 hardcoded the name and reduced the font size for all codes. This version reduces the font when needed and provides an optional number of digits on the config page.

• 2^32 = 4294967296. The first digit is 0-4 so no one would really use 10 digits. This should cover any use.