Add read-binary! function

[burinc]

Add basic support for read-binary option.

Note that only read is supported so no write-binary! is implemented.

• Improve the link to specific section of the document for data-sources
• Add basic test by reading the Geni logo and confirm the meta-data

[codecov-io]

Codecov Report

Merging #313 (85b96ec) into develop (314a300) will decrease coverage by 0.032%. The diff coverage is 87.500%.

@@              Coverage Diff               @@
##            develop      #313       +/-   ##
==============================================
- Coverage   100.000%   99.967%   -0.033%     
==============================================
  Files            36        36               
  Lines          3070      3078        +8     
==============================================
+ Hits           3070      3077        +7     
- Misses            0         1        +1     

Impacted Files	Coverage Δ
src/clojure/zero_one/geni/core.clj	100.000% <ø> (ø)
src/clojure/zero_one/geni/core/data_sources.clj	99.512% <87.500%> (-0.488%)	:arrow_down: