Ignore SIGINT sent to an interactive repl server

Unfortunately, even though *pump-in* is false, the server subprocess
still gets the SIGINT when you hit <ctrl-c>. REPLy used to take care of
that by registering a handler itself, but it's a ClassLoader leak, as
discussed in trptcolin/reply#127, so I removed it. But now subprocess
servers crash instead of gracefully being interrupted.

Here we're careful only to register the process in the specific case
where we're responsible for both the input and the server.

Pro: REPLy clients avoid classloader leaks.
Con: All REPLy clients have to implement this same sort of handling, but
only (?) if they're running in a subprocess.
Document some common issues with GPG on Mac OSX

Deals with this issue: https://github.com/technomancy/leiningen/issues/1386
fix #1581 - do not try to create an existing directory
Remove citations and change 'voice'

Solutions via people from this issue: https://github.com/technomancy/leiningen/issues/615
Remove inline code blocks
Merge pull request #1576 from Christopher-Bui/patch-1

Document some common issues with GPG on Mac OSX
avoid creating dir only if it is \".\"
Merge pull request #1582 from kumarshantanu/master

fix #1581 - do not try to create an existing directory
when opening a JarFile, report name of file in any errors

java.util.JarFile. can fail without reporting the name of the file it's
operating on. If you have a jarfile that isn't a valid zip, this can be
confusing.
Merge pull request #1584 from MichaelBlume/report-bad-filename

when opening a JarFile, report name of file in any errors
Merge pull request #1570 from technomancy/ignore_sigint_in_repl_subprocess

Ignore SIGINT sent to an interactive repl server
Default to warning when version ranges are present.

Fixes #1374.
Clarify :mirrors naming requirement.

Fixes #1579.

[ci skip]
Fix change task test to not be overly specific.
Fix the test that's been failing on Travis

The problem was something to do with the project map being too
bare. Switching to `defproject` fixes it.
fix 'lein vcs tag' to actually use prefix.
remove heardcoded dash from prefix.
Merge pull request #1591 from xsc/fix/vcs-tag

Let 'lein vcs tag' actually use the supplied Prefix
Added a warning message when the Main-Class does not exist within the jar file.
Added a unit test for the Main-Class warning in write-jar