fix false URLs

Author: jnavila

book/04-git-server/sections/gitlab.asc

@@ -39,7 +39,7 @@ image::images/gitlab-menu.png[The ``Admin area'' item in the GitLab menu.]
 Users in GitLab are accounts that correspond to people.
 User accounts don't have a lot of complexity; mainly it's a collection of personal information attached to login data.
 Each user account comes with a *namespace*, which is a logical grouping of projects that belong to that user.
-If the user +jane+ had a project named +project+, that project's url would be http://server/jane/project[].
+If the user +jane+ had a project named +project+, that project's url would be `http://server/jane/project`.
 
 [[rgitlab_users]]
 .The GitLab user administration screen.
@@ -56,7 +56,7 @@ This is obviously a much more permanent and destructive action, and its uses are
 ===== Groups
 
 A GitLab group is an assemblage of projects, along with data about how users can access those projects.
-Each group has a project namespace (the same way that users do), so if the group +training+ has a project +materials+, its url would be http://server/training/materials[].
+Each group has a project namespace (the same way that users do), so if the group +training+ has a project +materials+, its url would be `http://server/training/materials`.
 
 [[rgitlab_groups]]
 .The GitLab group administration screen.

book/08-customizing-git/sections/config.asc

@@ -239,7 +239,7 @@ We'll demonstrate setting up the Perforce Visual Merge Tool (P4Merge) to do your
 If you want to try this out, P4Merge works on all major platforms, so you should be able to do so.
 I'll use path names in the examples that work on Mac and Linux systems; for Windows, you'll have to change `/usr/local/bin` to an executable path in your environment.
 
-To begin, download P4Merge from http://www.perforce.com/downloads/Perforce/[].
+To begin,  https://www.perforce.com/product/components/perforce-visual-merge-and-diff-tools[download P4Merge from Perforce].
 Next, you'll set up external wrapper scripts to run your commands.
 I'll use the Mac path for the executable; in other systems, it will be where your `p4merge` binary is installed.
 Set up a merge wrapper script named `extMerge` that calls your binary with all the arguments provided:

book/09-git-and-other-scms/sections/client-hg.asc

@@ -34,7 +34,7 @@ $ pip install mercurial
 (If you don't have Python installed, visit https://www.python.org/[] and get it first.)
 
 The last thing you'll need is the Mercurial client.
-Go to http://mercurial.selenic.com/[] and install it if you haven't already.
+Go to https://www.mercurial-scm.org/[] and install it if you haven't already.
 
 Now you're ready to rock.
 All you need is a Mercurial repository you can push to.

book/B-embedding-git/sections/jgit.asc

@@ -154,7 +154,6 @@ Many other commands are available through the Git class, including but not limit
 This is only a small sampling of JGit's full capabilities.
 If you're interested and want to learn more, here's where to look for information and inspiration:
 
-* The official JGit API documentation is available online at http://download.eclipse.org/jgit/docs/latest/apidocs[].
+* The official JGit API documentation is available online at https://www.eclipse.org/jgit/documentation[].
   These are standard Javadoc, so your favorite JVM IDE will be able to install them locally, as well.
 * The JGit Cookbook at https://github.com/centic9/jgit-cookbook[] has many examples of how to do specific tasks with JGit.
-* There are several good resources pointed out at http://stackoverflow.com/questions/6861881[].