Add PR and Issues IDs hyperlinks to CHANGELOG

[julian-poidevin]

To ease readability, hyperlinks may be added to the CHANGELOG to refer to related PR and Issues.
Right now the issues numbers are non-clickable:

Here's a example on how I would like the CHANGELOG to be :

V0.2.4

• Updated some embedded SVD files !138 (Thanks https://github.com/clementperon for your PR)
• Fixed parsing of some SVD files !141 (Issue #126 - Thanks https://github.com/mryndzionek for your PR)
• Fixed issues with race condition on start up and improved OpenOCD support !151; Should fix issues #147, #149 and #150. A huge thanks to https://github.com/haneefdm for this PR, and his ongoing support on the project.
• Ability to specify port ranges used !146 (Thanks https://github.com/blckmn for your PR)

[Marus]

Good point - will try to keep this in mind for the future - and update the existing ones when I have time.