Make nth return default value when out of bounds
Shadow '+' to handle string/list concatenation
Merge pull request #642 from microamp/issue-639

Fix #639: Shadow '+' to handle string/list concatenation
Fixed (read) docs as mentioned inn #641
Merge pull request #645 from Foxboron/read-doc-fix

Fixed (read) docs as mentioned inn #641
Include optional arg in docs (nth)
Merge pull request #641 from microamp/issue-638

Fix #638: Make nth return default value when out of bounds