[READY] Update ycmd

[micbou]

Include the following changes:

• PR [READY] Let ycmd check rustup configured path as the last means to finding rust src path ycmd#785: automatically find Rust sources through rustup;
• PR [READY] Do not return canonical type if identical to type ycmd#835: do not return canonical type if identical to type in C-family languages;
• PR [READY] Allow system boost and system libclang usage ycmd#837: improve support of system Boost and system libclang on Gentoo;
• PR [READY] Improve Red Hat and CentOS detection ycmd#840: improve Red Hat and CentOS detection;
• PR Consider header file entries in compilation db ycmd#842: consider header file entries in compilation database;
• PR [READY] Improve completion of include statements in C-family languages ycmd#843: improve completion of include statements in C-family languages;
• PR [READY] Rename completer options ycmd#851: rename completer options in installation script;
• PR [READY] Only include one of the possible mac toolchains in the include paths ycmd#855: only include one macOS toolchain.

Update documentation according to PRs ycm-core/ycmd#785 and ycm-core/ycmd#851.

Close #2379.

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This change is 

[codecov-io]

Codecov Report

Merging #2804 into master will not change coverage.
The diff coverage is n/a.

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##           master    #2804   +/-   ##
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  Coverage   92.42%   92.42%           
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  Files          20       20           
  Lines        1954     1954           
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  Hits         1806     1806           
  Misses        148      148

[puremourning]

with one comment for consideration. Thanks for doing this!

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Reviewed 3 of 3 files at r1.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

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README.md, line 1067 at r1 (raw file):

rustup component add rust-src

to get the code. YCM will find its location automatically. Otherwise, download

I would add ‘to get the code’ before the colon like ‘add the following command to download he code:’ ...

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Comments from Reviewable

[micbou]

Reviewed 1 of 3 files at r1, 2 of 2 files at r2.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

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README.md, line 1067 at r1 (raw file):

Previously, puremourning (Ben Jackson) wrote…

I would add ‘to get the code’ before the colon like ‘add the following command to download he code:’ ...

Done.

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Comments from Reviewable

[bstaletic]

, but I'll let @puremourning trigger @zzbot.

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Reviewed 1 of 3 files at r1, 2 of 2 files at r2.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

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Comments from Reviewable

[puremourning]

perfect. @zzbot r+

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Reviewed 2 of 2 files at r2.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

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Comments from Reviewable

[zzbot]

📌 Commit 81be23b has been approved by puremourning

[zzbot]

⌛ Testing commit 81be23b with merge 48e3f2c...

[zzbot]

☀️ Test successful - status-appveyor, status-travis
Approved by: puremourning
Pushing 48e3f2c to master...