doc: Cleanup output of new PIM-EVPN doc

[donaldsharp]

The PIM-EVPN doc was not rendering very well on the
website. So Update documentation to allow it to render
better.

Signed-off-by: Donald Sharp sharpd@cumulusnetworks.com

[LabN-CI]

💚 Basic BGPD CI results: SUCCESS, 0 tests failed

Results table

_	_
Result	SUCCESS git merge/4187 e2b5880
Date	04/23/2019
Start	13:50:13
Finish	14:13:53
Run-Time	23:40
Total	1813
Pass	1813
Fail	0
Valgrind-Errors	0
Valgrind-Loss	0
Details	vncregress-2019-04-23-13:50:13.txt
Log	autoscript-2019-04-23-13:50:58.log.bz2
Memory	449 446 374

For details, please contact louberger

[NetDEF-CI]

Continuous Integration Result: SUCCESSFUL

Congratulations, this patch passed basic tests

Tested-by: NetDEF / OpenSourceRouting.org CI System

CI System Testrun URL: https://ci1.netdef.org/browse/FRR-FRRPULLREQ-7337/

This is a comment from an automated CI system.
For questions and feedback in regards to this CI system, please feel free to email
Martin Winter - mwinter (at) opensourcerouting.org.

---

CLANG Static Analyzer Summary

• Github Pull Request 4187, comparing to Git base SHA e400cd8

No Changes in Static Analysis warnings compared to base

12 Static Analyzer issues remaining.

See details at
https://ci1.netdef.org/browse/FRR-FRRPULLREQ-7337/artifact/shared/static_analysis/index.html

[LabN-CI]

💚 Basic BGPD CI results: SUCCESS, 0 tests failed

Results table

_	_
Result	SUCCESS git merge/4187 e7a664c
Date	04/23/2019
Start	15:30:17
Finish	15:54:01
Run-Time	23:44
Total	1816
Pass	1816
Fail	0
Valgrind-Errors	0
Valgrind-Loss	0
Details	vncregress-2019-04-23-15:30:17.txt
Log	autoscript-2019-04-23-15:31:02.log.bz2
Memory	442 434 375

For details, please contact louberger

[NetDEF-CI]

Continuous Integration Result: SUCCESSFUL

Congratulations, this patch passed basic tests

Tested-by: NetDEF / OpenSourceRouting.org CI System

CI System Testrun URL: https://ci1.netdef.org/browse/FRR-FRRPULLREQ-7339/

This is a comment from an automated CI system.
For questions and feedback in regards to this CI system, please feel free to email
Martin Winter - mwinter (at) opensourcerouting.org.

---

CLANG Static Analyzer Summary

• Github Pull Request 4187, comparing to Git base SHA e400cd8

No Changes in Static Analysis warnings compared to base

12 Static Analyzer issues remaining.

See details at
https://ci1.netdef.org/browse/FRR-FRRPULLREQ-7339/artifact/shared/static_analysis/index.html