Research/use idle sockets

[hollodotme]

Proposed Changes

• Adding socket status: INIT, IDLE & BUSY to check for idle & reusable sockets
• Reset response property of Socket class when a new request is performed
• Do not disconnect & remove socket from list after response was received
• Remove sockets only from list, if it's not usable anymore (e.g. timed out or closed)
• Refactor socket list to an internal collection in order to cleanup operations on the socket list
• Tests for the newly introduced socket methods
• Tests for the newly introduced socket collection
• Tests for the re-using of idle sockets

[codecov]

Codecov Report

Merging #33 into development will increase coverage by 6.51%.
The diff coverage is 88.03%.

@@                Coverage Diff                @@
##             development      #33      +/-   ##
=================================================
+ Coverage          82.45%   88.97%   +6.51%     
- Complexity           178      209      +31     
=================================================
  Files                 13       14       +1     
  Lines                456      517      +61     
=================================================
+ Hits                 376      460      +84     
+ Misses                80       57      -23

Impacted Files	Coverage Δ	Complexity Δ
src/Client.php	48.57% <58.33%> (+4.66%)	38 <0> (-7)	⬇️
src/Sockets/Socket.php	90.37% <92.1%> (ø)	73 <12> (?)
src/Sockets/SocketCollection.php	98.18% <98.18%> (ø)	26 <26> (?)

---

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 9596249...fe4b9c1. Read the comment docs.