Enhancement: Implement FormatSniffer

[localheinz]

This PR

• disables the mb_str_functions fixer
• implements a FormatSniffer

Follows #10.

[codecov]

Codecov Report

Merging #12 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##             master    #12   +/-   ##
=======================================
  Coverage       100%   100%           
- Complexity       32     42   +10     
=======================================
  Files             7      8    +1     
  Lines            78    102   +24     
=======================================
+ Hits             78    102   +24

Impacted Files	Coverage Δ	Complexity Δ
src/Format/FormatSniffer.php	100% <100%> (ø)	10 <10> (?)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update a4320e4...652e26b. Read the comment docs.