This PR adds a note to clarify that the ML API for ALS only supports integers for user/item ids, and that other types for these columns can be used but the ids must fall within integer range.
(Refer [SPARK-14891](https://issues.apache.org/jira/browse/SPARK-14891)).
Also cleaned up a reference to `mllib` in the ML doc.
## How was this patch tested?
Built and viewed User Guide doc locally.
Author: Nick Pentreath <nickp@za.ibm.com>
Closes#13278 from MLnick/SPARK-15502-als-int-id-doc-note.
## What changes were proposed in this pull request?
Correct some typos and incorrectly worded sentences.
## How was this patch tested?
Doc changes only.
Note that many of these changes were identified by whomfire01
Author: sethah <seth.hendrickson16@gmail.com>
Closes#13180 from sethah/ml_guide_audit.
This documents the implementation of ALS in `spark.ml` with example code in scala, java and python.
Author: BenFradet <benjamin.fradet@gmail.com>
Closes#10411 from BenFradet/SPARK-12247.
