resolve security advisory

[martinfrances107]

I love this project but - When I run cargo audit

I get this warning

Updating crates.io index
Scanning Cargo.lock for vulnerabilities (64 crate dependencies)
Crate:     time
Version:   0.1.45
Title:     Potential segfault in the time crate
Date:      2020-11-18
ID:        RUSTSEC-2020-0071
URL:       https://rustsec.org/advisories/RUSTSEC-2020-0071
Severity:  6.2 (medium)
Solution:  Upgrade to >=0.2.23
Dependency tree:
time 0.1.45
└── chrono 0.4.26
    └── theta-chart 0.0.5

error: 1 vulnerability found!

I have just filed an issue with "time" crate requesting than an security warning already fixed in the main branch be published to crates.io

downstream security wasning

The fix here when that is complete will be simple.

[LangPham]

Temporarily update to version 0.0.6 while waiting for chrono to fix.

• I disbable default-features of chrono to fix