[backport] Update AnyVals.scala

Corrected api doc for >> operator to say it bit-shifts right rather than left, and fills the left bits rather than the right bit

(cherry picked from commit 17b99e2587251cdb02e9d96fc2f87143be3160b8)
[backport] Make comment consistent with code

(cherry picked from commit fd001811c662f6daecf91319b36c1ad14a87ff72)
[backport] Update PartialFunction documentation to include the fact that the caller is responsible for checking 'isDefinedAt'

(cherry picked from commit f7d2cec3a0c31836747a25e3cc5949d1f3cbdff4)
[backport] Update PartialFunction documentation to include the fact that the caller is responsible for checking 'isDefinedAt'

(cherry picked from commit 455bcd65c055119f928b3367839f0093cf0e251a)
[backport] Revised comment to appeal to lchoran's and som-snytts comments

(cherry picked from commit 71bc2e5f4c49463a754a6f23e3abd2d27467fca4)
[backport] som-snytt's update to wording

(cherry picked from commit 80a9e908fd7b591a6fe452d908407d537675a999)
[backport] Change StringContext scaladoc

See e2a3498 commit message for explanation

Explicit private declaration better than implicit
Thanks to @som-snytt

(cherry picked from commit d071abe8dd9035d8dd246ecb6b207e584b6437fa)
[backport] Added example to Option.collect method.

(cherry picked from commit 6c698089aeb55e649a65dd7ae1bce2b4514ee865)
[backport] SI-8705   Added example to Option.contains method.

(cherry picked from commit 1e2a21681a4a55469faa59b07473a3b269e70258)
[backport] [scaladoc] Changed align of example code to Option.contains and Option.collect methods.

(cherry picked from commit e3311073bbad6f6f0dfdd3ea09628d324b4b3614)
[backport] Fixes first sentence delimiters

Scaladoc places the first sentence in the method summary table and index. The first sentence is defined as the sequence of chars up to the first period (not as in JavaDoc where the sentence ends with the first period *followed by a blank*). As a consequence, the clause starting with `i.e.` is interpreted as sentende delimiter. This request replaces `i.e.` with `i&period;e&period;`. Alghough a valid HTML code, I do not know whether this change is compatible with other tools. And I assume that this is not the only source file affected.

(cherry picked from commit c2e4da674d8c40e2d220854a966b0510fb6d459e)
[backport] Did not know of the fix for SI-8672. Followed the recommendation given by som-snytt.

(cherry picked from commit ec4abf5483e890976ae460252e80a66a95674e61)
[backport] Fix scaladoc typo

(cherry picked from commit 0a1694d8048f01b7f0812cedaa341813e9044e7f)
[backport] Fixed mathematically wrong statement in the documentation of scala.math.PartialOrdering.

- Previous (misleading) documentation suggested that a partial ordering *is* an equivalence relation. This has now been clarified.
- Existing documentation on properties of partial orderings (reflexive, transitive, antisymmetric) had several formatting inconsistencies that have now been remove.

(cherry picked from commit 528df5becee03175e7462b64d7c22460cc5992f7)
[backport] Refactored example to Option.collect method.

(cherry picked from commit 7cca7635b392cb533d0f8e26b74d7362c0dd3891)
[backport] Fixes cut sentences in the generated scaladocs

This commit changes all first sentences of library functions which
contain `i.e.` or `e.g.` and adds a `,` to prevent that the scaladoc
summary sentence is cut after this abbreviation.

This is possible as pull/3824 fixed how Scaladoc parses the first
sentence of a method description into a sumary sentence(now the first
sentence has to end with a dot followed by whitespace).

Only docs in the core library are changed (src/library/**/*.scala)
and only if they occur in the first sentence.

Review by @heathermiller

(cherry picked from commit 72721ff5dd06dea1235ecb71acae0bd61aee4814)
[backport] Update javadoc tag to new scaladoc tags.

(cherry picked from commit 68b16a0992877b4ebbb7c967804edbb72c05ceb5)
[backport] Rewrite explanation of doc-source-url option more clearly, and fix encoding to show euro-sign correctly.

(cherry picked from commit 13054daa658484df30b71447dbe684f475537252)
Merge remote-tracking branch 'upstream/2.11.x' into backports

Conflicts:
	src/library/scala/util/matching/Regex.scala
Merge pull request #3947 from lrytz/backports

Backporting from 2.12.x to 2.11.x