Update simplelog requirement from 0.11.2 to 0.12.0

[dependabot]

Updates the requirements on simplelog to permit the latest version.

Changelog

Sourced from simplelog's changelog.

v0.12.0

- Replaces the semingly unmainted chrono library with the time crate.
- Addresses through this update 
    - RUSTSEC-2020-0159 (chrono)
    - RUSTSEC-2020-0071 (time)
- `ConfigBuilder::set_time_to_local` is replaced by `ConfigBuilder::set_time_offset_to_local`.
    - This function requires the new (and by default activated) `local-offset` feature.
    - This function may fail, for more information read the docs.
    - simplelog will not determine the local offset dynamically anymore, but only once, when this config option is set.
        - Due to safety reasons there is no way to provide this property currently.
- `ConfigBuilder::set_time_offset` now takes a `time::UtcOffset` instead of a `chrono::FixedOffset`.
- `ConfigBuilder::set_time_format` has been replaced by three new variants
    - `ConfigBuilder::set_time_format_rfc2822` sets the time format to use the format described by rfc2822.
    - `ConfigBuilder::set_time_format_rfc3339` sets the time format to use the format described by rfc3339.
    - `ConfigBuilder::set_time_format_custom` sets the time format to a custom time format best created using `time::macros::format_description`.
        - Runtime provided time format configuration is possible, but difficult due to lifetime constraints.
        - Fixing this will require a solution to https://github.com/time-rs/time/issues/429
    - *Note*: The default format is unchanged "[hour]:[minute]:[second]"

v0.11.0

- Add colored log levels using `ansi_term` (PR [#88](https://github.com/drakulix/simplelog.rs/issues/88), credits to @manio)
- Add target padding (PR [#85](https://github.com/drakulix/simplelog.rs/issues/85), credits to @bytebeamio)
- Add optional color and style support using `paris` crate (PR [#84](https://github.com/drakulix/simplelog.rs/issues/84), credits to @manio)

v0.10.2

- Fix flushing with `BufferedStandardStreams` (PR [#82](https://github.com/drakulix/simplelog.rs/issues/82), credits to @mrkline)

v0.10.1

- Fix TermLogger performance using `termcolor::BufferedStandardStream` (PR [#80](https://github.com/drakulix/simplelog.rs/issues/80), credits to @mrkline)
- Add write thread name support for `termlog` (PR [#76](https://github.com/drakulix/simplelog.rs/issues/76), credits to @zeroflaw)

v0.10.0

- Fix wrong argument naming (PR [#70](https://github.com/drakulix/simplelog.rs/issues/70), credits to @scvalex)
- *Breaking*: More color customization options (PR [#72](https://github.com/drakulix/simplelog.rs/issues/72), credits to @mrkline)
- Clarify docs on config levels

v0.9.0

- Add customizable level label colors (PR [#69](https://github.com/drakulix/simplelog.rs/issues/69). credits to @JarrettBillingsley)
- Remove unneeded TermLogError
- Future-proof config by adding `#[non_exhaustive]`
- Fix compiling with minimal-versions

v0.8.0

- Switch from `term` to `termcolor` (PR [#59](https://github.com/drakulix/simplelog.rs/issues/59). credits to @raybritton)
- Fix typo in docs (PR [#58](https://github.com/drakulix/simplelog.rs/issues/58), credits to @anthonyjmartinez)
- Switch default padding to `Off`. Padding is annoyingly controversal, just set it to whatever you prefer, if you want it.

v0.7.6

- Derive `Clone`,`Copy`,`PartialEq`,`Eq`,`Debug` and `Hash` for `TerminalMode`. (PR [#56](https://github.com/drakulix/simplelog.rs/issues/56), credits to @panhania)

... (truncated)

Commits

• 95275c8 v0.12.0
• f137eb4 Merge pull request #101 from jacobtread/patch-1
• ba17254 Merge pull request #99 from zjp-CN/master
• 44a294f Merge pull request #95 from Drakulix/fix/chrono_dep
• d925791 Out of place space?
• 81c6293 Merge pull request #100 from rusty-snake/patch-1
• d49c3fd config.rs: docs: Add intra-doc links
• 568309c add demo for paris feature
• 40808ea fix the problem of macro hygiene when paris is enabled
• cf8fc32 fix TestLogger
• Additional commits viewable in compare view

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[anweiss]

Requires Rust 1.59.0

[dependabot]

A newer version of simplelog exists, but since this PR has been edited by someone other than Dependabot I haven't updated it. You'll get a PR for the updated version as normal once this PR is merged.